Historic, Archive Document
Do not assume content reflects current scientific knowledge, policies, or practices.
LiPPiNCOTT’s Home Manuals
EDITED BY BENJAMIN R. ANDREWS, Ph.D.
Teachers College, Columbia University.
SUCCESSFUL CANNING AND PRESERVING
PRACTICAL HAND BOOK FOE SCHOOLS, CLUBS, AND HOME USE
BY
OLA POWELL
U. S. DEPARTMENT OF AGRICULTURE, ASSISTANT IN HOME DEMONSTRATION WORK IN STATES RELATIONS SERVICE
J, COLORED PLATES, 164 ILLUSTRATIONS IN TEXT
PHILADELPHIA & LONDON
J. B. LIPPINCOTT COMPANY
COPYRIGHT, 1917, BY J. B. LIPPINCOTT COMPANY
Eiectrotyped and Printed by J. B. Lippincott Company The Washington Square Press, Philadelphia, U. S. A.
OCT 1 6 1917
1 f>S
o
TO
YOU WHO ARE STRJVING TO “ MAKE YOUR BEST better” MY WORK IS SYMPATHETICALLY DEDICATED
PREFACE
The canning and preserving of food products is an important factor in household management and of even greater importance in national economy, since the conservation of foodstuffs, from the time of production and natural time of consumption to a later time, makes for a more varied and adequate diet, and that secured at a lower economic cost. Practical success in canning, preserving, drying, and brining turns upon the proper applica- tion of the principles of science involved. The great necessity for scrupulous care in every step of the whole process is imperative. A worker who follows scientific principles and is watchful of sanitary conditions will have results that are uniform and sat- isfying. It is easy to talk of science in the abstract as applied to such problems, but unless one can show just how this science demands that the processes be conducted in order to secure suc- cess, such applied ‘‘science” is mere pretence.
Women and girls are now facing a most wonderful oppor- tunity for service in aiding to produce and conserve foods not only for home consumption, but by increasing the commercial products for export to Europe. The responsibility of wisely utilizing the yield from greatly increased acreage rests in good part upon the women and girls. Their work can be simplified and made more effective by wisely applying scientific methods.
It is imperitive not only to produce and conserve supplies of food, but also to select the most economical means of keeping the various food products. In view of these facts, the suitability of canning in comparison with other means of keeping food must be considered. Since the public has been convinced of the con- venience of handling and serving canned foods, canning has be- come the most widely used and popular means of preserving large quantities of fruits and vegetables. Some products could be stored and sometimes prepared more economically in the home
vii
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PREFACE
if conserved by other means of preservation, such as drying, brining and storing.
Preserving foods by drying is a very desirable means and one which is especially important to practice when there exists a shortage of tin cans and when glass containers have advanced a great deal in price.
Vegetables, such as sweet corn, green string beans, peas, and fruits such as cherries, berries, peaches, and tigs, can be dried, and in this state they will furnish variety and serve as a substi- tute for canned foods. If properly dried and stored many foods are attractive and wholesome. Such vegetables as cauliflower, cabbage, cucumbers, and chayotes are better saved in brine than canned. Many other vegetables may also be kept in brine. Legumes like peas and beans, root crops like carrots and beets, while attractive when canned in a succulent stage, are more nutritious and more economically stored when mature.
The use of various foods in the home should be planned in advance, so there will be no waste, at the same time having food for each meal economically combined and balanced so as to nourish each member of the family properly.
This book has been written to help rather than to shine, and if it does help, the author will be content.
July, 1917.
Ola Powell.
ACKNOWLEDGMENTS
The author wishes to acknowledge her appreciation to those who have read and criticized the manuscript; to Mr. 0. B. Mar- tin, Assistant in Charge of Demonstration Club Work, U. S. De- partment of Agriculture, for his interest and encouragement during the entire preparation of the manuscript; to Miss j\Iary E. Creswell, Assistant in Home Demonstration Work, U. S. De- partment of Agriculture, for reading and criticizing the manu- script, and for the interpretation of the Home Demonstration Work given in Chapter XIX ; to Miss Rhea C. Scott, Specialist in Home Demonstration Work in Louisiana, for her sympathy, in- terest, and assistance throughout the preparation ; to Mr. Charles T. Dearing, Assistant Horticulturist, U. S. Department of Agri- culture, for reading and criticizing the chapter on ‘‘ Fruit Juices”; to Dr. M. N. Straughn, Scientific Assistant, Bureau of Chemistry, U. S. Department of Agriculture, for reading and correcting the chapter on ‘‘Jelly Making,” also for the table for using the Brix hydrometer in fruit juices for jelly making; to ]\Iiss Caroline L. Hunt, Scientific Assistant, Office of Home Eco- nomics, U. S. Department of Agriculture, for Chapter XVII, “Uses of Fruits and Vegetables in the Diet”; to Mrs. Jane S. IMcKimmon, State Home Demonstration Agent in North Carolina, for chapter on “The Business Side of Canning”; to Frantz P. Lund, Specialist, States Relations Service, Department of Agri- culture, for valuable contributions to chapter on “ Drying Fruits, Vegetables, and Herbs”; to jMr. H. C. Thompson, Horticulturist, Bureau of Plant Industry, Department of Agriculture, for criti- cizing Chapter XV and for the information on storing garden and orchard products; to Dr. L. A. Round, Scientific Assistant, Bureau of Chemistry, Department of Agriculture, for criticizing chapter on “Pickling,” and for furnishing the table for making brines; to Dr. Albert Mann, Plant Morphologist, U. S. Depart- ment of Agriculture, and Dr. Albert Brubaker, Jefferson ^Medical
IX
X
ACKNOWLEDGMENTS
College, Philadelphia, for criticizing the chapter on '‘Bac- teriology as Applied to Canning”; to Miss Sarah Wilson, Drexel Institute, Philadelphia, for criticizing the manuscript and pre- paring the list of questions at the end of each chapter from the point of view of a Home Economics teacher ; to Mr. F. H. Hall, New York Experiment Station, for the recipe “Making Cider Vinegar on the Farm”; to the U. S. Department of Agriculture for photographs, material quoted, and ideas obtained from the following publications: Department Bulletin No. 241, “Studies on Fruit Juices”; U. S. Yearbook, 1914, “Apple Syrup and Com centrated Cider,” by H. C. Gore; Farmers’ Bulletin No. 644. “Manufacture and Use of Unfermented Grape Juice,” by George C. Husmann; Farmers’ Bulletin No. 183, “Meat on the Farm: Butchering, Curing and Keeping,” by Andrew Boss; for circu- lars from the States Kelations Service, Extension Work in the South, prepared by Miss Mary E. Creswell and Miss Ola Powell; also to Major Lawrence Foot for the use of Arkansas Extension Bulletin, “ How to Cure, Smoke, and Keep Hams, Shoulders, and Bacon”; to Mr. G. L. Tiebout, Louisiana State University, for results of experiments in cauliflower brining; to Mr. J. A. Red- head, Louisiana State University, for recipe on pepper chow- chow; to Mrs. Dora D. Walker, Assistant State Agent in Home Demonstration Work in South Carolina, for recipe on “Pimiento Ketchup”; to Mrs. Margaret Jonas, Assistant State Agent in Home Demonstration Work in Kentucky, for recipe on “Can- ning Cucumber Slices. ’ ’ A few of the recipes for use of canned goods in this book are adapted from such authors as Miss Anna Barrows, Miss Helen ]M. Spring, and Miss Fannie Farmer; some are from private sources, and others are original.
The following books especially were consulted during the preparation of the material : ‘ ‘ Household Bacteriology, ’ ’ by Estelle D. and Robert Earle Buchanan; “Canning and Preserv- ing of Food Products with Bacteriological Technique,” by E. W. Duckwall; “Complete Course in Canning,” by C. L. Denning; “Canning and How to Use Canned Foods,” by A. W. and K. G. Bitting; also The Trade, Baltimore, and other magazines were consulted.
ACKNOWLEDGMENTS xi
Assistance is acknowledged from all of the commercial con- cerns which have so generously contributed illustrations and in- formation. Thanks are also due and gratefully given to many others who have aided by advice, information, and encourage- ment.
To Miss Carrie Harrison, of the U. S. Department of Agri- culture, is due the phrase used as the dedication, “To you who are striving to make your best better” — which expresses the sentiment to-day animating the tens of thousands of canning club girls. South and North and West, as it also expresses the perennial spirit of the American housewife.
Ola Powell.
July, 1917.
CONTENTS
CHAPTER page
I. History of the Development of Scientific Canning 1
II. Bacteriology as Applied to Canning 15
III. Preparation and Equipment 36
IV. Canning in Tin 59
V. Canning in Glass 71
VI. Processing — Hot-Water Bath 77
VII. Processing at High Temperature 87
VIII. Fruit Juices 93
IX. Fruits for Canning 124
X. Vegetables for Canning 133
XI. Preserves 148
XII. Marmalades, Jams and Conserves 163
XIII. Jelly Making 174
XIV. Pickling 189
XV. Drying Fruits, Vegetables and Herbs 228
XVI. Preservation of Meats 256
XVII. Use of Fruits and Vegetables in the Diet 275
XVIII. Canning Club Organization 282
XIX. The Business Side of Canning 300
XX. Teaching Canning and Related Activities 316
Appendix 346
Index 353
ILLUSTRATIONS
COLOR PLATES
PLATE PAGE
Preserves Frontispiece
I. Attractive Packs of Canned Fruits 120
II. Attractive Pickle Packs 204
III. Food Chart 276
ILLUSTRATIONS IN TEXT
FIG.
1. Type of Can Used about 1889 3
2. Manufacturing Tin Cans To-Day 4
3. Cliart Showing Comparison of Value of >\Ieat Products hy States
in 1899 and 1909 7
4. A Chart Showing Comparison of Value of Canned and Preserved
Products by States in 1899 and 1909 8
5. A Processing Device for Home Canning Proposed in 1889 10
6. Parasitic Organisms 10
‘7. Aspergillus fumigatus (Appears on Tomato Sauces and Preserves) 18
8. Bacillus Found on Tomatoes, Showing Flagellae 19
9 Penicillium glaucum (x500) 20
10 Various Stages of Brewers’ Yeast 21
11. Bacillus hutyriciis (Rods and Spores Found in Corn) 24
12. Anaerobic Pea Bacillus 25
13. Bacillus megatherium (Vegetating Forms as Found in Cans of
Peas ) 20
14. (A) Can Bursted from Pressure of Gas Generated, (B) A Normal
Can, (C) A Swell 27
15. Testing the Jar Seal 28
10. A Group of Useful Utensils for Washing, Peeling, Coring, Grating
and Slicing Fruit and Vegetables 37
17. Special Equipment Necessary to Obtain Most Successful and Accu-
rate Results 37
18. Utensils Used in Blanching and in Cooking 38
19. The Processor and Rack with Jars Ready to be Sterilized 39
20. Tongs for Handling Hot Cans 40
21. Cooperative Canning Minimizes Labor; Canning Club Girls in
Anson County, N. C., at Work 41
22. North Carolina County Agents at Peace Institute, Raleigh, N. C. 42
XV
XVI
ILLUSTRATIONS
23. A Homemade Fly-Trap 43
24. Mississippi Club Girls Building a Fly-Trap for Out-of-Door Can-
ning 44
25. A Convenient Arrangement for Out-of-Door Canning 45
26. Canning Out of Doors, State Normal School, Harrisonburg, Va 46
27. Canning Tomatoes from the Scholarship Plot, State Normal School,
Harrisonburg, Va 47
28. A Kerosene Stove which Burns a Gas Flame for Heating Soldering
Tools 47
29. A Fire-Pot Burning Corn-Cobs for Heating Tools. A Gasoline
Fire-Pot or Charcoal Bucket May also be Used 48
30. A Folding Portable Canner 49
31. Standard Sizes of Tin Containers 49
32. Size of Cans Used for Household Purposes 50
33. Hand Machine for Sealing Special Sanitary Cans 51
34. Capping Steel and Tipping Copper 52
35. A Group of Jars for Household Use 53
36. Commercial Jars for Special Products ; 54
37. Appropriate Containers for Exhibit Purposes 55
38. Individual Containers 56
39. Box of Rubbers and a Jar 57
40. Sorting and Grading Tomatoes. 61
41. Uniform Tomatoes Together 62
42. Scalding Tomatoes, Using a Square of Cheesecloth 63
43. Capping 65
44. Tipping 65
45. Heating, Tinning, Capping, and Tipping 66
46. Students Learning to Can in Tin 67
47. Labelling 68
48. Sterilizing Glass Jars 72
49. Packing Uniform Pieces of Rhubarb 72
50. Well-Packed Jar of Peaches. 73
51. Paddles : . . . 74
52. Canning in Glass on Campus of Peabody College for Teachers,
Nashville, Tenn 75
53. An Ordinary Bucket Used as a Processor 78
54. A Wash-Boiler with False Bottom Makes a Convenient Processor. 78
55. Canner Made of Tubs for Outdoor Use 79
56. A Homemade Canner with Brick Fire-Box and Tub 80
57. Showing Construction of a Hot-Water Canner 81
58. A Kerosene Stove Burning a Gas Flame 82
59. A Folding Two-Burner Gasoline Stove 82
60. Tank Fitting Inside 82
61. A Steam Retort for Home Canning 88
ILLUSTRATIONS
XVll
62. A Steam Retort for Home Canning 88
63. Another Type, Known as the Water Seal Canner 88
64. Another Steam-Pressure Outfit for Home Canning 89
65. Pressure Cooker 90
66. Commercial Retorts where the Steam is Piped in from the Boiler 91
67. Household Fruit- Juice Press 94
68. Cloth Press Being Twisted 95
69. Construction of a Homemade Fruit Press 96
70. Fruit Press Ready for Use 97
71. Fruit Press in Use 97
72. A Homemade Fruit-Juice Filter 98
73. Bottling Fruit Juice 99
74. Making Sealing Wax... 101
75. Screw-Cap Bottle 102
76. A Hand Bottle Sealing Machine 102
77. Utensils Used in Making Muscadine Syrup 107
78. Making Vinegar on the Farm 116
79. Fig Packs 127
80. Attractive Packs of Canned Fruits: {a) Berries, (6) Pears, (c)
Fruit Salad 127
81. A Balling Hydrometer 128
82. A Brass Cup which Can be Used in Place of Glass Cylinder for
Testing Density of Syrup and Brine 129
83. A Demonstration in Canning, Florida 130
84. Cleansing Rubber Ring 131
85. Fancy Packs of Canned Vegetables: (A) Baby Beets, (B) Carrot
Circles, (C) Log-Cabin Pack of Beans, (D) Concentrated Soup Mixture, (E) Okra 136
86. Roasting and Packing Pimientos 141
87. Attractive Pepper Packs 142
88. Tomatoes Packed for Salad 144
89. Vegetables Packed Fresh for Soup Mixture 146
90. Packing Watermelon Rind Preserves 149
91. A Chemical Thermometer — Centigrade 150
92. Cooling and Plumping Preserved Fruits 151
93. Packing Preserved Figs, Walton County, Fla 152
94. Only Freshly Picked Berries Should be Preserved 153
95. A Steam- Jacketed Preserving Kettle 161
96. Guava Paste, Served with Clieese and Crackers 172
97. A Commercial Jelly Strainer Placed on a Chair Back 175
98. A Commercial Jelly Strainer Placed on a Table 175
99. Alcohol Test for Pectin in Fruit Juices 176
100. Testing Fruit Juice for Pectin 176
101. A Saccharometer Floating in a 250-c.c. Cylinder 177
XVlll
ILLUSTRATIONS
102. Jellometer for Testing Fruit Juices in Jelly Making 180
103. Making Strawberry and Orange Pectin Jelly 181
104A. First Test Shows Drops of Syrup 182
104B. Finished Test Shows Jelly Flaking or Sheeting from the Paddle. 182
105. A Coffee Pot is a Convenient Utensil for Melting and Pouring the
Paraffin 184
106. A Few Good Glasses of Jelly Ready to Store 185
107. Fancy Jellies 187
108. Brine Hydrometer 192
109. Brining Equipment 193
110. Sealing a Crock with a Band of Cheesecloth Dipped into Boiling
Paraffin 195
111. A Few Pickle Packs 197
112. Preparation of Vegetables for Mixed Pickles 200
113. A Fancy Pack of Mixed Pickles 202
114. Packing Pickles with Paddles 203
115. Making Dixie Relish and Stuffing Pepper Mangoes 204
116. Brining Onions 216
117. Drying Raspberries 232
118. A Homemade Drier 232
119. A Reflector Drier 234
120. {A) Homemade Cook-Stove Drier, (B) Sectional View, Showing
the Passage of the Heated Air 235
121. Sliced Apples on a Wooden Tray 238
122. Drying Figs in California 239
123. Drying Peaches in California. Trays Stacked for Finishing Off. 239
124. Cutting a Pork 261
125. Trimming Hams 261
126. Picnic Hams Properly Trimmed 261
127. A Well-Trimmed Ham 262
128. A Well-Trimmed Breakfast Bacon 262
129. Grinding Sausage Meat the Second Time after Seasoning is Added. 267
130. Roast with Vegetable Madedoine Garnish 278
131. Fruit Macedoine 279
132. A Glass of Currant Jelly 279
133. Canned Asparagus and Pepper Salad 280
134. Log-Cabin Salad Made from Canned Beans 280
135. The Home Women, as Described by D. F. Houston, Secretary of
Agriculture 286
136. A Comfortable Garden Uniform 287
137. Another Style of Garden Uniform 288
138. Garden Uniform 289
139. A North Carolina Canning Club at Work 304
140. Properly Labelled Jars 308
ILLUSTRATIONS
XIX
141. Standard Packs in Tin 308
142. North Carolina County Agent Attending Canning School and Con-
ference, 1015 313
143. A Cultivated City Vacant Lot in Philadelphia 322
144. A Training Farm in Cleveland, Ohio 323
145. A Cooperative Neighborhood Garden in Philadelphia, Pa 324
140. A Tomato Plot in Geauga County, Ohio 325
147. Harvest Home Exhibit, Willard School, Cleveland, Ohio, 1910... 320
148. Harvest Home Exhihit in Willard School, Cleveland, Ohio, 1911. . . 327
149. A Ten-Year-Old Member with Her Exhibit from a Tiny Plot,
18x22 Feet 328
150. Senior Class at Harrisonburg Normal School, Va., Cultivating and
Spraying Their Plants 329
151. Staking and Tying Plants 329
152. Prize Winning Short Course Girls Pruning Tomato Plants 330
153. Senior Class Receiving Instructions in Canning 331
154. Students’ Display of Canning Products from the Scholarship Plot. 331
155. Tomato Plot Cultivated by Senior Class at Hattiesburg Normal
School, Mississippi 332
150. Plan of Building Used for C'anning at State Industrial College,
Denton, Texas 332
157. A North Carolina Exhibit of Fir.st-Year Products 335
158. A Parish Exhibit in Louisiana 330
159. A Miniature Exhibit Suggested as a Plan for a Fair 337
100. A Carefully Planned Exhibit 338
101. Judging Canned Tomatoes and Beans 339
102. This Cow Has Proved to be a Wonderful Prize for this Tennessee
Girl 340
103. Gardening Set: Kneeling Pad and Apron for Tools 341
SUCCESSFUL
CANNING AND PRESERVING
CHAPTER I
HISTORY OF THE DEVELOPMENT OF SCIENTIFIC
CANNING
Most great industries have existed in some form for a long period of time, but the preservation of foodstuffs by canning is distinctly a modern art. Men turned their thoughts at a very early time to devising means of preventing foods from spoiling, but until the beginning of the nineteenth century the only methods employed to this end were drying, pickling, smoking, and preserving in sugar.
French Government First to Discover Method. — The wars of Napoleon were directly responsible for the discovery of the efficacy of the hermetic sealing of foods in order to keep them. Near the end of the eighteenth century a prize was offered by the French Government for the most practical method of pre- serving foods for sea service and military stores. M. Nicholas Appert, of Paris, was stimulated by this offer of a reward and began experimenting. He worked from 1795 until 1809, when he submitted to his government a treatise on the means of pre- serving foods. During this year he was awarded the prize of twelve thousand francs. In 1810 he published the results of his experiments.
Appert’s Method. — His method was to enclose fruit, after heating it, in a glass bottle, which was then corked and sub- jected to action of boiling water. The bottle was placed in a water-bath and was heated very gradually for varying lengths of time, depending upon the character of the food. Appert did not know why foods kept when treated according to his method. He believed that air was the destructive agent and that its exclusion
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SUCCESSFUL CANNING AND PRESERVING
alone would preserve food which had been cooked. In his treatise he wrote: ^‘Absolute privation of the contact of external air is necessary after the internal air is rendered of no effect by proper application of heat by means of a water-bath. ’ ’
Past Experiences a Background for Work. — Appert’s wide experience in life excellently equipped him to solve the problem to which he had applied himself so devotedly. He had for nearly fifty years been dealing with various lines of food preservation, working as a pickier, a preserver, an expert confectioner, a brewer, a distiller, and a chef. He continued his efforts, using many different products, and so perfected the art of canning in glass that it is difficult to surpass it even in these times with all our modern appliances. His simple utensils and process-room might provoke a smile to-day, for science had in his day not really determined why canned food kept ; though his explanation has proved to be wrong, his methods, oddly enough, worked.
Investigations Made by Guy Lussac. — Conclusions drawn by Guy Lussac, an eminent French chemist, who was employed by his government to investigate this matter, coincided with what appeared to be the controlling factor in the practice of can- ning. He reported that spoiling of food was due to a series of oxidation changes, and that by excluding the air these changes could be prevented and the food saved. This theory was ac- cepted, and the true explanation of the matter was not known until the advent of the new science of bacteriology. Since the principle of Appert’s methods has been shown by time and ex- perience to be correct, it is that on which all canning and pre- serving have since been done. He is regarded as the father of an art which has proved a boon to all mankind. The French Government has erected a monument to perpetuate his memory. His method was so simple that others began using it very soon, and before 1830 it was put into commercial practice. Appert used an open water-bath for heating his bottles, and this method is one in common use to-day in home canneries. This information on canning was desired primarily for military and naval stores, but the advantage of having food preserved in this manner at- tracted considerable attention to its use in the home.
HISTORY OF SCIENTIFIC CANNING
3
Canning Begun in England. — In 1807 a paper was submitted by Mr. Sadding to the English Society of Arts, under the title “A Method of Preserving Fruits Without Sugar for House and Sea Stores. ’’ It is believed that this knowledge of the general prin- ciples was obtained from Appert while Sadding was travelling in France. About the same time Peter Dur- rand obtained a patent in England for preserv- ing meat, fruit, and vegetables in tin cans.
DEVELOPMENT OF THE TIN CONTAINER
The canning indus- try from this time on depended a great deal on the can; in fact, it took its name ‘ ‘ can- ning’^ from it. The ap- paratus for manufactur- ing tin cans was at first very crude. The bodies were cut with shears and the side seams made with a plumb joint and then soldered together.
A weight was pulled up to the ceiling and al- lowed to drop upon a ^ — ^bout i889.
sheet of tin in order to cut tops and bottoms of the cans. The die was cast on the under side of the weight, and the opposite die was cast in a piece of metal below. The forming of these pieces depended on the weight being properly guided, therefore the proc- ess was slow and difficult. Heads or caps were made to set into the body and were soldered in place by hand in a very primitive
4
SUCCESSFUL CANNING AND PRESERVING
way. Necessity has never more truly proved its title, ‘‘The Mother of Invention,’’ than in the canning line (Fig. 1). These cans were about the size of a No. 2 can, except that they were taller. From the crude homemade experimental apparatus there have been developed for the purpose of the canner all sorts of machinery and appliances. Now all parts of the can are made by labor-saving machinery and put together by machinery. This method reduces their cost enormously (Fig. 2). Commercial
Fig. 2. — Manufacturing tin cans to-day. (Heinz Co.)
houses abandoned glass in favor of tin cans because they would withstand extremes of temperature and the initial cost was less. The transportation both ways on the tin can was less costly and the loss from breakage was eliminated. Tin is probably the con- tainer used almost universally by canners now, although glass is popular in the more exclusive canning and preserving kitchens where very choice special products are put up into fancy packs.
The Real Cause of Putrefaction. — During the time of Tyndall and Pasteur, 1822 to 1895, the real cause of putrefaction was
HISTORY OF SCIENTIFIC CANNING
5
determined to be living microorganisms which come in contact with the material which “spoils.” To these men belongs the honor of discovering the fundamental principles involved. Now- adays it is understood that the mere presence or absence of air in a can is a matter of no importance in itself. Air plays no im- portant part in putrefaction save as a carrier of living things, which are commonly and popularly spoken of as germs, microbes, microorganisms, or bacteria. All of these terms are used some- what indiscriminately and all mean practically the same thing.
DEVELOPMENT OF COMMERCIAL CxVNNING IN AMERICA
The canning industry was established in the United States by Ezra Daggett, in 1819. He had learned the trade before emi- grating to this country, and packed salmon, lobsters, and oysters in New York. The records show that William Underwood packed preserves and table condiments in glass as early as 1821, in Bos- ton, and in 1835 he packed tomatoes in glass. The records also show that William Underwood shipped his goods to South America in 1821. In 1837 Isaac Winslow began experimenting with the canning of com in Portland, Maine. There is probably no earlier record of canning in tin in this country than the work of Isaac Winslow. Corn was first canned on the cob. This proved unsatisfactory on account of the bulk, and it was thought the cob absorbed some of the sweetness from the kernels. Maine was the home of the corn canning, and is still so considered. The first cannery in Baltimore was opened about 1840. The canning of com, tomatoes, and fruits was started in Cincinnati, Ohio, about 1860. The growth of the industry was very rapid. New canneries sprang up like mushrooms in various parts of the coun- try, and unskilled men vied with the older packers in the quantity put out. This rapid growth resulted in the formation of Can- ners^ Associations, the development of which led to new and better methods of work.
The question of preservation of food is one of the most inter- esting and important in the whole field of applied science. H. L. Russell, of the University of Wisconsin, was the first man in this country to apply the science of bacteriology to canning, in 1895,
6
SUCCESSFUL CANNING AND PRESERVING
and in 1896, Prof. S. C. Prescott, of the Massachusetts Institute of Technology, and W. L. Underwood, of Boston, began investiga- tions regarding the bacteriological technique of canning. Until this time the commercial art of canning was a mixed lot of theory hedged about by mystery.
Theory of Canning Not Understood. — Factories were jeal- ously guarded. It was almost impossible for an outsider to gain admission. The canner really knew so little about the science that he felt compelled to guard carefully his ignorance. He tried to throw a glamour of secrecy over nearly every move- ment simply through caution to protect what little good informa- tion he possessed regarding the process of canning. The uncer- tainty and the possibilities that losses might occur were a constant source of worry and uneasiness to a great many who were en- gaged in the canning business. The general public had a very vague knowledge in regard to bacteria. Most people associated them only with disease. Canners were loath to have the subject of canning connected with germs, because they believed this would frighten people, who would then not wish to eat any more canned goods. If a season came in which bacteria seemed un- usually prevalent, the canners considered it most mysterious and attributed it to the ‘ ‘ strange season. ’ ’ Since science has brought to us the knowledge of microorganisms the lines of attack have become more clearly marked, and with the modern weapons to combat the foe we can fight the war against bacteria with safety and assurance of success. The principal weapon of defence against bacterial action is the practice of most scrupulous cleanli- ness ; just as modern surgery depends upon absolute cleanliness. Like most other manufacturing industries carried on by enter- prising men, the process of canning has undergone complete change as the scientific principles involved have come to be under- stood and to be given a controlling power over the practical proc- esses involved.
Location of Industry (Figs. 3 and 4). — Large quantities of vegetables, meat, and fish are preserved along the Atlantic Coast ; much of the salmon supply is canned in Oregon and Washington ; meats are put up largely in Chicago and Kansas City, and fruits
HISTORY OF SCIENTIFIC CANNING
7
and vegetables of the highest grade are packed in California, Hawaii, and New York. Maryland and New Jersey rank very high in the production of canned tomatoes. Maine and Illinois lead in corn canning. The development in the canning industry in the ten-year period is shown in the accompanying charts and is largely due to improved machinery.
MILLIONS OF DOLLARS
Fig. 3. — Chart showing comparison of value of meat products by states in 1899 and 1909, (Thirteenth Census of U.S., Vol. VIII, 1910.)
A striking illustration of growth in the canning industry is the rapid development of the pineapple canning in the Hawaiian Islands indicated by the following table:
1901 2,000 cases
1908 410,000 cases
1913 1,667,000 cases
This volume of business is the combined output of ten sepa- rate companies. These results show the quick appreciation of a really good product by the consuming public. In the first can-
8
SUCCESSFUL CANNING AND PRESERVING
ning large quantities of juice were lost when the prime ripe fruit was sliced. Eecently it has been discovered that the juice con- tains seven per cent of sugar and can be concentrated and used for syrup in canning pineapple, thus saving the purchase of large quantities of sugar.
Better Equipment Invented. — When corn canning was first begun, the corn was cut from the cob with a common case-knife ;
MILLIONS OF DOLLARS
California New Vbrh Maryland Washinyton^ PennsylOam^ Indiana Maine Illinois Massachuseds\ Michigan (Vis cons in Ohio
BBF
Nevl Jersei/ Wm Oregon loWa Delaware Kentackij (Virginia Missouri Colorado Minnesola Ulah
W
H?
F
F
P
iii
AX
IHHi 1909
mUM fC'99
Fig. 4. — A chart showing comparison of value of canned and preserved products by states in 1899 and 1909. (Thirteenth Census of U. S., Vol. VIII, 1910.)
then came the use of a curved form shaped to the ear. At this stage of development “cutters” were the most numerous body of workmen about the factory. For instance, in 1869, 800 hands were employed in a factory : 375 were cutters and about 100 busk- ers. Machines run by hand came in about 1875. Power machines came into use about 1886. Much improvement has been made on all machinery since that date. In canning corn, for example, among the most important machinery are those which husk the
HISTORY OF SCIENTIFIC CANNING
9
corn, take off the silk, cut kernels from the cob, fill the cans, seal the cans, put on labels, etc. Different machines are made to fit into the work of other machines so the various processes of han- dling one product will be continuous. These machines are now perfected in all details and are operated automatically. The capacity is immense for carrying products through the different departments in a very short time.
Processing Methods (Fig. 5). — In the early days of this in- dustry the open-kettle method was used. The highest obtainable temperature was 212° Fahrenheit, the temperature of boiling water. It was soon realized that a higher temperature would kill more “germs” and insure more successful results in a shorter length of time. A little later a higher degree of temperature was secured by the addition of common salt to the water-bath. Fol- lowing this another method of obtaining a higher degree of heat came into favor. It was found that by adding chloride of cal- cium to water the specific gravity of water was increased and a temperature of 240° Fahrenheit was obtainable without ebulli- tion. The advantage claimed for this method was that it was fuel-saving and labor-saving. Under this process, however, the cans became discolored and considerable expense was incurred in cleaning them. With the coming of the ‘‘steam- jacketed” copper kettles and the ‘ ‘ closed-process ’ ’ kettle these previously described methods of sterilizing were abandoned, except for the plain water- bath, which is still in use. The steam- jacketed kettle is one in which a kettle is surrounded by a metallic chamber like the com- mon double-boiler kettle, except that the outer chamber is air- tight and superheated steam is piped into it from a boiler, thus raising the temperature of the cooking kettle considerably above 212°. Such steam-jacketed kettles are commonly used in large- quantity cookery, as in hotel kitchens and industries like dyeing and soap making, as well as in canning. The closed-process kettle is simply a kettle for boiling which can itself be closed tightly so as to prevent all escape of steam; the heat which ordinarily escapes from the water as the steam arises is thus kept within the water and in the superheated body of steam in the closed cham- ber above it, and so the temperature rises above 212° With the
10
SUCCESSFUL CANNING AND PRESERVING
introduction of steam retorts in 1897 the time for sterilizing was shortened. Next came the present style of kettle and dry steam.
Latest Processor. — The agitating cooker is perhaps the latest development. Bulky starch products are poor conductors of heat, and it requires a long time for the heat to penetrate to the center of the contents. The time for processing can he greatly reduced by causing the cans to roll over and over in such a man-
Fig. 5. — A processing device for home canning proposed in 1889.
ner that the liquid present within each can will he carried more quickly through the mass and the contents will he gently moved to the inside surface of the can, where they become heated more rapidly. It is necessary that this agitation he slow and even.
Other Labor-saving Devices. — There are machines for almost every step of the handling of different fruits and vegetables for canning; conveyors, sheet-iron tunnels where jets of water are constantly running to wash the product, sorters, peelers, slicers, fillers, and cappers; these and many other machines are avail-
HISTORY OF SCIENTIFIC CANNING
11
able, and all are labor-saving and space-saving as well. The result of this application of machines and power is that a great quantity of products can be handled in a very short time.
Greater Demand for Canned Foods. — In 1890 there were about one thousand establishments engaged in this industry and the value of the output was a little less than $45,000,000. In 1916 the output for domestic consumption was thirteen times this amount. The consumption of canned products has increased yearly, largely because the prices have been reduced as the com- mercial process has been perfected, thus coming within reach of a larger number of people. It has been said that in 1857 a quart of tomatoes sold for 50 cents and a quart of peaches for $1. Nathan Winslow sold to Samuel S. Pierce, of Boston, one dozen canisters of preserved corn for $4 in February, 1848. The public has been informed through reports and investigations and through the advertising world that the conditions under which reliable concerns work are sanitary and that canned food prod- ucts are as desirable in their place as are fresh foods ; the more the public becomes aware of these facts the greater is the demand for this class of food. Eeduced prices and a buying public educated to the real value of canned foods explain the greater demand for them.
Consumption and Estimated Value of Canned Foods in 1916. — A report which was given at the annual meeting of the National Canners’ Association in Louisville, Ky., in February, 1916, will be of interest here to show, to some extent, the use of canned food in the United States. Three billion cans of food are retailed yearly at about $600,000,000. The consumption of com is estimated to be 100,000,000 cans annually ; of peas, 200,000,000, and of tomatoes, 350,000,000. New York City spends yearly at retail over $64,000,000 for milk, $45,000,000 for bread, $45,000,- 000 for eggs, and for canned goods over $150,000,000 — almost as much as for milk, bread, and eggs combined. In 1916 the report of the Canning Club girls and Home Demonstration Clubs in the South showed 3,318,481 containers put up for home use and for the market. In the North and West 7903 Canning Club members put up 201,306 containers in 1916. This is, of course, only a very
12
SUCCESSFUL CANNING AND PRESERVING
small percentage of the full amount of such products put up in the homes of the country. The economic significance of the use of canned foods has grown to such proportions that it cannot be ignored by the housewife or by the nation.
It is important to have vegetables and fruits in the diet, but it is impossible to have them fresh at all seasons, especially with the difficulty of distribution and transportation of foods in thickly populated areas. The problem of extending the supplies from season to season must necessarily be met by preservation of foods. The composition and their importance in the diet place them among staple foods rather than as accessories in the diet. A judicious amount of fruits, vegetables, meats, and whole cereals mingled with the canned products will doubtless furnish the necessary supply of “vitamins,” growth-promoting substances, which recent investigations indicate are essential to good health.
United States Government Publication. — The United States Government has many persons employed to work out some of the problems that perplex the preservers of food. These people have been studying for years and experimenting along these lines. Bul- letins have been printed on the subject which can be secured free, or at a very small cost. Many housekeepers are now eagerly seeking this information. Laws also have been passed to attempt to regulate the methods of preparation of canned foods. People have gradually acquainted themselves with the ways in which bacteria work for our good or ill, and it is no longer necessary to whisper when discussing their effect on canned goods. It is known that useful “germs” greatly outnumber the harmful ones. Since we could not exist without the action of bacteria, we must regard them as our friends rather than our foes, even though there are a few species which might do us injury.
QUESTIONS
1. What proof can you give that canned goods hold to-day a large place
in the food supply of our large cities as well as in portions of the country remote from the centers of population?
2. Why is it impossible to collect statistics of the value of the foods
canned annually in the United States?
HISTORY OF SCIENTIFIC CANNING
13
3. Why is the study of the canning of foods a legitimate work for the
United States Government?
4. What large classes in the community may be helped by the knowledge
of canning disseminated by the government?
5. What forces have made possible the extensive use of canned foods?
6. What has determined the locations of the canneries?
7. State chronologically the different processing methods used, giving a
brief explanation of each.
8. What is the principle to which each process conforms?
9. To what science are we indebted for the explanation of the results ob-
tained in canning?
10. What is the meaning of putrefaction? What is its cause?
11. To whom are we indebted for the explanation of putrefaction? To
whom indebted for the application of scientific explanations to can- ning?
12. To whom are we indebted for tlie discovery of canning? What his-
torical events led to this discovery? Give approximate date.
BIBLIOGRAPHY
1. Bitting, A. W. and K. G., “ Canning and How to Use Canned Foods,’’
1916. National Canners’ Association, Washington, D. C. 30 cents.
2. Bureau of the Census, Statistics for Canning and Preserving, 1910,
Thirteenth Census of the United States Manufacturers, 1909. Can be purchased from the Superintendent of Documents, Government Printing Office, Washington, D. C. 5 cents.
3. Corbett, Florence R., ‘‘ Fruits and Vegetables,” Technical Education
Bulletin No. 18, February, 1913. Teachers College, Columbia Uni- versity, New York City, N. Y. 10 cents.
4. Deming, Olin Lee, “ Science and Experiment as Applied to Canning,”
1902. Sprague Canning Machinery Company, Chicago, 111.
5. Duckwall, Edward Wiley, “ Canning and Preserving of Food Products
with Bacteriological Technique,” 1905. Pittsburgh Printing Com- pany, Pittsburgh, Pa. $5.
6. Fisher, Irving, and Fisk, E. L., “How to Live,” 1915. The Funk &
Wagnalls Company, New York City, N. Y. $1.
7. Hunt, A. L., “ Canning and Preserving,” Twelfth Census of the United
States Manufacturers, vol. 9, part 3, 1900, pages 461 to 514. Super- intendent of Documents, Government Printing Office, Washington, D. C.
8. ^Mendel, Lafayette Benedict, “ Changes in the Food Supply and
Their Relation to Nutrition,” 1916. Yale University Press, New Haven, Conn. 50 cents.
9. Mendel, Lafayette Benedict, “ Cliildhood and Growth,” 1906. The
F. A. Stokes Company, New York City, N. Y. 60 cents.
14
SUCCESSFUL CANNING AND PRESERVING
10. Sherman, Henry Ceapp, Food Products/" 1914. The Macmillan Com-
pany, New York City, N. Y. $2.25.
11. Shriver, J. Alexus, “Pineapple Canning Industry of the World,”
Bureau of Foreign and Domestic Commerce, U. S. Department of Labor.
12. The Pierce Publishing Company, Inc., The National Food Magazine,
45 West Thirty-fourth Street, New York City, N. Y. $1.50 a year.
13. The Trade Company, Baltimore, Md., The Canning Trade (a magazine),
almanac of the canning industry. $3.
14. VuLTE, Herman Theodore, and Vanderbilt, Sadie Bird, “ Food In-
dustries,’" 1916. Chemical Publishing Company, Easton, Pa. $2.
15. Ward, Artemas, Grocers’ Encyclopaedia, 1911. Artemas Ward, 50
Union Square, New York City, N. Y. $10.
CHAPTER II
BACTERIOLOGY AS APPLIED TO CANNING
Scientists have established beyond a doubt that the decom- position of food is due to the presence of living organisms which cause fermentation and putrefaction. These organisms are molds, yeasts, and bacteria and belong to the lowest order of plants. The presence of all or any of these types of germs on food is the principal cause of its spoiling. Similar microorganisms exist in teeming millions and are present everywhere. They are in the water we drink, in the soil, floating about in the air we breathe, and on all objects. All of these except mold are so minute as to be invisible without the aid of a microscope. Molds, yeasts, and bacteria differ from the plants with which we are more familiar in that they are unable to manufacture their own food out of the air and the soil as the green plants do. These types contain no chlorophyll or green coloring matter, and must therefore get their food from substances already built up by higher plants or animals. These colorless plants are generally grouped by botanists under the division fungi,” though the bacteria are strictly separated from the yeasts and molds. Both the chlorophyll-bearing and the colorless plants embrace those that are parasites and others that are saprophytes. The para- sites live upon live animals and plants; the saprophytes live upon dead animals and plants, and it is this class, therefore, which concerns us in canning.
Some people do canning and preserving of foods successfully with little knowledge of these germs, but to know something about these minute forms of life, which are so abundant everywhere, will make the work more interesting. When it is understood why foods keep, uniform results may be more easily obtained.
Molds. — The molds, unlike yeasts and bacteria, are visible to
15
I
■f
Fig. 6. — Parasitic organisms. In the following figures ha denotes aerial hyphae; sp. sporangium; zy, zygospore; ex, exosporium; my, mycelium; me, mucilage; c/, columella; en, endogonidia.
Fig. a. Spore-bearing hyphae of Mitcor, growing from horse-dung. Fig. B. The same, teased out with needles (A, 4). Figs. C, D, E. Successive stages in the development of the sporangium. Fig. F. Isolated spores of Mucor. Fig. G. Germinating spores of the same mold. Fig. H. Successive stages in the germination of a single spore. Figs. I, J, K. Suc- cessive phases in the conjugative process of Mucor. Fig. L. Successive stages obser\^ed during ten hours in the growth of a conidiophore of Penicilliumin an object-glass culture (D,4).
BACTERIOLOGY OF CANNING
17
the naked eye. They are considered first because most house- keepers and students in home economics are familiar with them in their growing stage. Molds require oxygen, considerable moisture and heat, and use sugar and starches as food ; moreover, they can grow in the presence of acids. They thrive in damp, dark places where there is little or no circulation of air. Because they have the ability to grow in acids molds readily attack fruits and to- matoes. At first in general appearance molds are gray, soft, and fluffy; later they show colors, as blue, green, brown, black, or yellow. The color appears when the molds are reproducing. Under a microscope the minute, thread-like mass of mold found upon jelly or bread shows a mycelium or root-like structure ex- tending into the food upon which it grows. The upward-growing branches bear special spore organs which contain thousands of seed-like spores. The spores drop from the mold plant and float unseen to other places. They grow with great rapidity. The kinds reproducing yellow and green spores are sometimes found on jellies, preserves, and dry meats. They are first green and then yellow. Brown mold is found in putrefaction of fruit. Cer- tain types of food materials, particularly the fruits, are most apt to be attacked by molds such as Penicillium and Aspergillus (Figs. 7 and 9 ) . These molds do not develop unless there is oxygen pres- ent. These mold spores being abundant in the air, it is impossible to leave food exposed without having a number of living spores fall upon it. If fruit is opened, partly used, and the jar is simply covered again, the fruit will soon mold, due to the mold spores which enter while it is open. If this fruit is to be kept it should be reheated and sealed to exclude the air. Usually the mold is confined to the surface, but the decomposition products of its growth frequently penetrate and flavor the whole mass. At one time it was believed by some housekeepers that a thick layer of mold on the top of crocks and jars containing jams and pre- serves was a good indication of its keeping, because this layer of mold excluded the air from the contents in the lower part of the container. When these jars were opened it was necessary to throw away several inches of the food which was next to the mold and sometimes nearly half of it. As the food stood with this 2
18
SUCCESSFUL CANNING AND PRESERVING
heavy layer of mold the odors and flavor permeated the balance of the contents of the jar, and the product when served was not so palatable and wholesome as it would have been had it been sealed air-tight and processed when flrst put up (Fig. 8). In addition, all waste of food is thus avoided.
Molds are easily killed by moist heat. A temperature of 160° to 180° Fahrenheit will be suflicient to kill all mold. When food
is sterilized, packed into jars or cans, and sealed immediately to protect it, mold will not appear so long as the containers remaiji air-tight. If the top of jelly is wiped off with alcohol this will kill some of the spores. Sometimes a circular disc of paper which has been dipped into alcohol is placed over the jelly before the cap is placed on the glass. Often a thin layer of melted paraffin is poured over the top of the jelly. Either method will kill any mold spores which might have fallen on the jelly while it was
Fig. 7. — Aspergillus fumigatus (appears on tomato sauces and preserves).
BACTERIOLOGY OF CANNING
19
open and cooling. Immediately after so treating the jelly it should be covered to exclude the air (Figs. 6 and 9).
Yeast. — The yeast plants are not difficult to control in can- ning. Yeasts are the natural agents which produce fermenta- tion. As this word is commonly used it refers to the process by
Fig. 8. — Bacillus found on tomatoes, showing flagellse, thread-like appendages.
which alcoholic liquors are produced from sugar solutions. Fer- mentation is the basis of producing stimulating beverages. Methods of raising yeast bread are also examples of fermentation. It is always the sugars present in these substances which undergo the fermentation.
Yeasts are one-celled plants. They reproduce by budding; that is, by the growth of a bud on the side of the cell. This bud
20
SUCCESSFUL CANNING AND PRESERVING
becomes fully developed very quickly and separates itself from the mother-cell, and after attaining the adult stage begins to reproduce itself in a similar manner. Yeasts, under adverse con- ditions, sometimes reproduce by forming spores within the cells. The cell bursts and the wind carries the spores everywhere. The use of yeast in bread making is familiar. When given food (in form of sugar) , warmth, moisture, and air, yeasts grow, breaking up the sugar and producing a gas, called carbon dioxide, and alcohol. Bubbles of this gas may be seen when a can of fruit fer-
ments. Since yeasts are abundant in the air and on the skins of fruits and vegetables, it is always necessary both to destroy them on the food being canned and to prevent their further en- trance into the sterilized foods by sealing the containers air- tight. Yeasts are easily killed by moist heat at a temperature of 160° to 190° Fahrenheit. Occasionally spores, which are more resistant than active plants, may be present. The organisms de- scribed above are not difficult to control (Fig. 10).
Bacteria. — Bacteria are the most serious foes to combat in canning because they are more difficult to kill by heat than either molds or yeasts. They are present everywhere in enormous
BACTERIOLOGY OF CANNING
21
numbers. They are also unicellular plants, but are smaller than yeasts. A young bacterium cell attains full size and acquires the capacity to reproduce itself much more rapidly than any other form of life. So rapid is their reproduction that a single bac- terium may produce millions more in a few hours. The rapidly multiplying bacteria often form more or less colorless viscous masses or a thin scum float- ing on the liquid in which they are growing. Similar masses form the green scum sometimes seen on stagnant water, due to the growth of a microscopic plant, the Spirogyra.
Bacteria require for their growth warmth, moisture, and food. Many kinds of bacteria prefer protein food. Food for bacteria is not necessarily of a highly complicated nature. Many species will find the right conditions for nourishment and growth if a small amount of protein and some water are present. Since few bacteria thrive in acids or in the presence of much sugar, their destruction is less difficult in fruits and tomatoes than in vegetables such as corn, peas, and beans, or in meats, which are the most difficult of all foods to can safely in the home.
Bacteria in the growing state can be killed by subjecting them to moist heat at boiling temperature for variable lengths of time. Moist heat is far more effective than dry heat. ]\Iany kinds of bacteria have the power under adverse conditions of producing spores which are much more resistant than the vegetative or ac-
Fig. 10. — Various stages in the development of brewer’s yeast, seen, with the exception of the first in the series, with an ordinary high power (Zeiss, D.4) of the microscope. The first is greatly magnified (Gundlach’s 1-16 immersion lens). The second series of four represents stages in the divi- sion of a single cell; and the third series a branching colony. Everywhere the light-areas indicate vacuoles.
22
SUCCESSFUL CANNING AND PRESERVING
tively reproducing form in which the bacteria ordinarily are found. Bacteria produce spores for the purpose of meeting un- favorable conditions, and in this resting stage the living matter may lie dormant for a long time, as it were, awaiting favorable conditions under which the vegetative rapid reproduction form can be resumed. These spores may be compared to the seeds of higher plants in their ability to withstand unfavorable condi- tions. While most of the bacteria which do not produce spores can be killed at a temperature of 140° to 180° Fahrenheit, it is a well-known fact that some spores are able to resist heat at boiling temperature for sixteen hours or more. Many bacteria show great adaptability to temperature conditions. Drying or dehydration for a long period of time will kill many organisms, but, on the other hand, spores may withstand drying for years. Sterilization to kill spores as well as the ordinary bacteria forms may be accomplished by applying boiling temperature for a cer- tain length of time on each of three successive days. Certain resistant spores will germinate within twelve to twenty-four hours after the first treatment ; but heating on the second day will kill these ; and the third treatment is a safeguard which will destroy all remaining ‘‘germs’’ in most cases. This intermittent or repeated sterilization with a constant temperature of 212° Fahrenheit is perhaps a safer method and will assure success more often than a single period of sterilization at the same tem- perature for a longer length of time.
Almost all the bacteria which are so resistant to heat when in the spore state are abundant in cultivated soil and therefore pres- ent in pods, husks, and different parts of such vegetables as com, peas, and beans, which contain food upon which the spore- bearing forms thrive. The presence of these bacteria upon the parts of vegetables to be canned is therefore almost inevitable. The difficulty of sterilization is increasingly great when such vegetables have been bruised, allowed to stand, or have in them decayed portions. When fruit skin is broken, molds fall to work and open the way for bacteria to enter and start the decay. If the juices of these plants become infected with spores of these various species, the problem of sterilization is more difficult.
BACTERIOLOGY OF CANNING
23
All bacteria in the spore state can also be destroyed by sub- jecting them to a temperature of 240° to 250° Fahrenheit, moist heat, but special apparatus, as the steam-pressure canner, is neces- sary to produce such temperatures. For this reason the method known as intermittent sterilization finds wide use among house- keepers and Canning Club members who do not possess steam- pressure canners. This method of fractional sterilization consists of applying boiling temperature to vegetables, already packed in glass or tin, for a certain period on each of three successive days, sealing the jar immediately after each boiling or '‘processing” if the lid has been loosened to take care of the expansion caused by the heat. Between each daily processing the containers are kept at ordinary temperatures, under which the spores not killed by boiling develop into the more easily killed vegetative or grow- ing state, which are then destroyed by the next period of boiling. If spores are present in the jars or cans, rarely do they fail to thus develop and be destroyed by the third processing (Fig. 11). For peas and corn, properly selected and handled carefully, proc- essing for one hour in a water-bath at boiling on the first day, and repeated on the second and third days, will ordinarily steril- ize these foods in quart jars or No. 2 cans. The flavor of such vegetables thus processed is considered by many to be finer than when the vegetables are subjected to very high temperatures, as in the steam-pressure cookers. Treatment for one hour on three successive days is perhaps the safest method to follow with hot- water canners, when canning such vegetables as sweet potatoes, peas, corn, beans, etc. It is dangerous to use minimum periods of processing, because during some seasons there are occasional ' ' out- breaks” where fields are infected with an unusual type or a larger number of bacteria than ordinarily exist. Some fertilizers cause the fibers of plants to toughen, and it is more difficult for heat to penetrate them, therefore a longer sterilization period is required. Every precaution should be taken to counteract the influence of such danger by cleanliness, careful handling, and rapid working from one stage to another during the entire process of canning.
Enzymes. — In addition to the action of “germs” or minute organisms, the spoiling of fruits and vegetables is hastened by
24
SUCCESSFUL CANNING AND PEESERVING
natural changes, which result from the action of enzymes or unor- ganized fermenting agents found in nature (the pepsin of the stomach is an illustration) which, while not cellular organism like bacteria, do break down and decompose foodstuffs. .These changes
Fig. 11. — Bacillus butyricus (rods and spores found in corn).
take place with varying rapidity in different foods and injure the quality of the food. The delicate flavors of many fruits are thus destroyed when they are allowed to stand too long, and become stale before being canned. This is an important reason why all
BACTERIOLOGY OF CANNTN^G
25
fruits and vegetables should be canned as quickly as possible after being gathered. The canner need not pay great attention to enzymes, because they are killed as soon as heated.
Classes of Bacteria. — A classification of bacteria in reference to their need of oxygen is especially helpful to the canner ; from this point of view, bacteria are of three classes :
1. Aerobic — require free oxygen.
2. Anaerobic — can live without free oxygen (Fig. 12).
Fig. 12, — Anaerobic pea bacillus.
3. Facultative (Aerobic, anaerobic) — can live with or without free oxygen.
Aerobic bacteria obtain the oxygen necessary for the process of multiplication from the air, and if the air is cut off they either remain dormant or die. Anaerobic bacteria obtain their supply of oxygen from organic compounds such as carbohydrates and pro- teins. This class sometimes causes more violent fermentation when forced to grow in the absence of free oxygen than when growing naturally; being deprived of free oxygen, the tearing
26
SUCCESSFUL CANNING AND PRESERVING
down of organic compounds is accomplished with great rapidity to supply the required oxygen, while the multiplication is les- sened. This fact accounts for the rapid spoilage of goods which have been improperly sterilized. The anaerobic bacteria bring about decomposition with the evolution of a large amount of gas (Fig. 13). This gas may accumulate in quantities sufficient to bulge and even to break the container in which it is sealed (Fig.
14) . When products in tin bulge from the presence of gas inside they are known as swells. ’ ^ Some bacteria have been described which bring about decomposition in vegetables and meat without evolution of gas. They give evidence of their presence by the development of peculiar odors and flavors. These are known as ' ' flat sours. ’ ’
A large percentage of losses in canned goods is due to the facultative anaerobes. The anaerobic bacteria, however, cause spoilage in many cases where others are destroyed because the an- aerobic belong to the soil and are spore-bearing and have the
Fig. 13. — Bacillus megatherium (the vegetating forms as found in a can of peas).
BACTERIOLOGY OF CANNING
27
power to withstand very high temperatures and afterwards de- velop. Most all of the anaerobes are known as bacilli; that is. they are rod-shaped.
Facultative aerobic or facultative anaerobic bacteria belong to a class which accommodate themselves to whatever condition in which they may be placed :
Facultative aerobes are anaerobic by nature, but will grow in an aerobic state ; that is, in air.
Facultative anaerobes are aerobic by nature, but will grow in an anaerobic state ; that is, where air is excluded.
Fig. 14. — (a) Can bursted from pressure of gas generated: (6) a normal can, (c) a swell.
Nearly all bacteria found in improperly sterilized sealed con- tainers are spore-bearing organisms, either anaerobic or faculta- tive anaerobic. If there should happen to be a leak in the can, any variety may enter and set up decomposition. Non-sporu- lating varieties are always destroyed at boiling temperature (212° Fahrenheit) ; so unless there is a leak or the sterilizing is incom- plete, this variety will not be present.
A partial vacuum is an ideal environment for the growth of anaerobic bacilli, since free oxygen interferes with the multipli- cation of these germs. On the other hand, they require oxygen for growth, but they must obtain it by breaking down substances that contain oxygen in chemical combinations.
Partially cooked material offers a more suitable medium for these germs, because the cellulose or fiber is softened and there is
28
SUCCESSFUL CANNING AND PRESERVING
usually more surrac.c; (;x|>os(mI, and llui juic(is an; richer iu carbo- hydrate or album irious matter, as the case may be. The dan<^er from t[u;se bact(;ria is not so j^rcat when; absolute cleardiness is ex(;reis(;d arid waste matcr*ial is f)rof)erly disf)Osed of. Many bac- teria whicii an; caf>abb; of’ sc;ttin^ up putrefactive; f)rocesses will thrive luxuriantly on a variety of cooked foods, wlien, as a
rule, they will not ^^row readily on whole raw materials.
Perfect Seal Important. — Putrefaction is sometimes found in
im[)(;rf(;ctly seal(;d and sterilized canned meats arid vegetables, ^fhis may be dm; to insufficient sterilization or to leaky cans. In the; pre>e;e;ss of putrefaction there are varie)us f)te)maine;s anel te)xic poise)us fe)rrneel which sometimes cause considerable tre)uble.
Testing the Seal. — (a) In glass. After fruits anel vegeta- })le;s an; eanneel anel set asiele until e;ntirely colei, the jars may be teste;d by removing the clamp anel atte;mpting to lift the lid from the jar. If the liel comes off, the jar was either not properly sealed or the; contents are fermenting and may have to be; diseareleel. If the; lid remains tight, the e;hances are that the; eeintents are keeping (Fig. 15). When faulty sealing alone e;xists jars may be reproce;sse;el and the contents saved. However, pre)tein foods arc sometimes attackeel by bacteria which thrive without the pre;se;ncc of air, and which decom- pe)se canned feieids without producing any gas. When these have ne)t been kille;d by processing, the food may appear good and the jar remain sealed when it is spoiled. These spoils in tin caused by bacteria which decompose food without form- ing gas are known as ^^flat sours”; with them the can is not bulged and shows no indication of spoiling. When such products are opened they are slimy and soft and they are acid to the taste.
15. — Teal-ing the jur acal.
BACTERIOLOGY OF CANNING
2D
(h) In tin. The time to detect the leak is when the can is first put into the sterilizer ; a shower of bubbles will be seen coming from the defective seal. If the can is removed immediately and retipped or capped, the contents may be saved in good condition. Occasionally the attempt is made to save defective cans, when they are detected after the processing, by reopening the tip hole, repairing the can, exhausting and reprocessing for the regular time, l^roducts handled by this careless method are very likely to cause most serious stomach and intestinal complications. This practice is a very dangerous one.
After cans are cooled, before stacking them, they are some- times tested by tapping the end of the can with a piece of metal. A clear, ringing sound indicates that the can is air-tight. If a dull sound is heard when the metal strikes the lid, the can should not be stored with tlie lot. A trained or experienced ear can very quickly detect from the sound when all is not well within.
Substances Injurious to Bacterial Growth. — Many bacteria in growing give rise to substances such as acids which are more or less injurious to the cell life. The accumulation of acids and other substances produced by bacteria interferes with the bacterial growth and their power of multiplication. We have examples of this in the ‘‘flat sours” and also in the brining of vegetables. The acid present when frothing ceases above the brined cucum- bers (lactic acid) is strong enough to kill most of the bacteria in the brine. It is this lactic acid which cures and keeps the vege- table if the air is excluded from it at this stage, and the forming of scum yeast at the surface of the brine is j>revented. Many manufacturers do not know that their brine contains acid, yet the instant it does not contain it the pickle begins to deteriorate. A full explanation of this process is given in the chapter on “Pick- ling,” page 190. One of the principal factors in the manufacture and preservation of sauer-krant is the development of lactic acid in quantities sufficient to act as a preservative. Bacteria, yeast, and molds are of value in preparation of foods such as vinegar, pickles, sauer-kraut, cheese, bread, and butter.
Methods of Preserving Foods. — Just at this point it may be helpful and interesting to consider methods of preserving food.
30
SUCCESSFUL CANNING AND PRESERVING
with a brief explanation of how each method accomplishes its pur- pose. To understand these fundamental reasons enables one to do canning and preserving more skilfully. The four methods com- monly used are preservation of food by drying, by preservatives, by heat, and by cold.
1. Preservation of Food hy Drying. — This method perhaps was one of the first known. In primitive times food was exposed to the direct rays of the sun for the purpose of drying it. This method is practiced at the present time, hut more frequently the product is subjected to a higher temperature. In the process of drying a considerable portion of water is eliminated and many of the organisms present are destroyed. Bacteria, yeast, and molds cannot develop when the moisture in any food is very much reduced below the original amount. The same is true when cer- tain disinfectants, such as smoke or the fumes of sulfur dioxide, are used in the cure. Meats and fish are frequently dried after a preliminary smoking or salting. Many food materials contain- ing an abundance of starch are sufficiently dried in the natural process of ripening and drying ; for example, certain nuts, such as chestnuts and the grains. Meats, meal, or fiour containing the same amount of moisture as raisins or prunes would quickly spoil. Fruits are usually readily preserved hy drying on account of their high sugar content. A dried or partially dried food should be sealed from the air to prevent gross contamination and to pre- vent moisture being absorbed due to its hygroscopic nature.
2. By Harmless Preservatives. — The most commonly used of these preservatives are salt, sugar, vinegar, and certain spices. In the presence of these, bacteria and yeast cannot grow success- fully. Products such as jellies, preserves, and pickles are easily kept because of the presence of one or more of these preservatives. While the sugar or spices used may prevent fermentation, molds are likely to occur on these foods unless sterilized and sealed to protect them from the air. This can be done with all of the prod- ucts, except jellies, by always processing and sealing after packing them into the containers. Jelly can be protected from mold by pouring over it a thin layer of melted paraffin when cold and covering it tightly.
BACTERIOLOGY OF CANNING
31
Sodium chloride (salt) is used for dry-salting fish and some- times other meats. The salt rapidly removes a part of the water and thus forms a medium which is not suitable for the growth of bacteria. This is a physical action, because it is brought about by greatly increasing the osmotic pressure. Some preservatives act chemically by direct antiseptic action upon the microorganisms. Preservatives that inhibit the growth of organisms by their chem- ical action as antiseptics belong in two classes: (a) those which are produced in the food as a result of fermentation of the food material being packed ; (&) those which are added directly to the food.
(a) Self-ferme7itation as Preservatioii. — Among the products in which preservation is achieved through the results of fermen- tation, in the process of curing, are pickles, olives, onions, sauer- kraut, cauliflower, and some pickled meats and various other raw materials. Lactic acid formed by the action of lactic acid bacteria upon sugar may develop in sufficient quantities in certain foods to preserve them indefinitely against further change if properly handled. The preservation of ensilage is largely due to the lactic acid and other acids which are formed during the process of curing.
(b) Preservmg powders and other chemicals added to foods for their preservation are considered detrimental to health. Not only are foods containing them in quantity less wholesome, but their use encourages carelessness and the putting up of food which is unsound and unfit to eat. Benzoic acid and salicylic acid and their salts, and formaldehyde, boric acid, and borates are some- times used. These compounds were purposely added by some of the early canners to shorten their sterilization period. Fortun- ately this method has largely been superseded by the more reliable and less expensive sterilization by heat only.
Some products, such as ketchups, sauces, and ‘‘fruit sundaes,’’ preserved with such chemicals as salicylic acid, benzoate of sodium, and borax, are still on the market. In many cases this method is used because the buyer prefers this class of goods, even when he knows that preservatives have been used to keep them in an unfermented state. Hotel and soda fountain trade some-
32
SUCCESSFUL CANNING AND PRESERVING
times prefers goods treated in this way because they will not spoil so soon after being opened. Sometimes tomato ketchup and fruits for sundaes will not keep for more than a week after the bottles or jars are opened. Frequently fermentation sets in about the fourth or fifth day, and mold will sometimes be visible to the eye in five or six days, if they have been sterilized by heat only. So long as the buyers ’ trade will accept food which is bought in large containers and has been allowed to stand around open for days at fountains and in hotels we may expect these preservatives to be used. This method is cheaper and requires less care and skill than the putting up of individual packages for each patron’s service. It is undoubtedly true that in a majority of cases it is advisable to preserve food materials whenever possible without the addition of antiseptics. They are unnecessary, and^ though the actual effect on the body of some is unknown, the^ burden of proof rests upon those who employ them.
3. By Means of Heat. — Two methods of heat application may be used — pasteurization or sterilization. In pasteurization the food is raised to such a temperature that the organisms of certain types, but not necessarily all organisms, are destroyed. This process is ordinarily applied to milk and cream and to certain alcoholic beverages, such as beer and wine. In some cases this results in a prolongation of the time during which the food may be used.
Sterilization by heat implies the use of a sufficient degree of heat to destroy all organisms present ; and when the entrance of other organisms into the sterilized food is prevented it may be preserved indefinitely. In the preservation of foods by heat it is necessary that a temperature be selected such that will destroy all organisms capable of producing undesirable changes and yet cause no undesirable changes to take place in the food itself. The antiseptic action of the acid found in some fruits and vege- tables is so increased by the temperature of boiling water that it quite certainly sterilizes the product. Foods containing a large proportion of sugars are also easily sterilized by boiling. Vege- tables such as corn and peas are much more difficult to preserve, inasmuch as they contain neither acid nor sugar in considerable
BACTERIOLOGY OF CANNING
33
quantities and are ordinarily infected with certain of the anae- robic spore-bearing bacteria which are capable of withstanding high temperatures.
The heat used in the preservation of food by sterilization pro- duces few changes other than those which would be accomplished by ordinary cooking. Heat will not injure the flavor very much unless it is prolonged.
Since sterilization or preservation by means of heat is the best way to retain the natural flavors and wholesome qualities of fruits and vegetables, this book will deal chiefly with this means of keep- ing these foods.
4. Preservation of Food in Cold Storage. — Practically all foods can be kept for a time by the use of low temperatures. Cold does not kill, but arrests the growth of organism. Some foods can be kept indefinitely by freezing. Meats may be held for some time at this temperature without deterioration ; in fact, for a time with marked improvement in tenderness and flavor. Some bac- teria may develop at temperatures below freezing-point of water, but not if they are in a medium which is solidly frozen. The length of time that food products may be kept in cold storage without danger to the health of the consumer is a disputed ques- tion, but it undoubtedly varies widely according to the nature of the food.
QUESTIONS
1. To what is the decomposition of foods due? Mention some changes
which take place during the decomposition of foods.
2. In what fundamental way do molds, yeast, and bacteria differ from
the plants with which we are most familiar ?
3. What is the distinction between parasites and saprophytes?
4. Describe briefly the characteristics of molds, including their necessities
for growth and their manner of growing and reproducing.
5. Why do molds readily attack fruits ?
0. How may mold be prevented from growing on the top of jelly? Explain
your answer.
7. What is yeast? Describe briefly the manner of its growth and the
necessities for it.
8. What are bacteria? State one way in which they differ definitely from
molds and yeast.
3
34
SUCCESSFUL CANNING AND PRESERVING
9. Why is it more difficult to can beans and meat than it is to can fruits and tomatoes?
10. What is meant by spore-bearing bacteria? How do spores differ from
bacteria in their tenacity of life?
11. Why are spore-bearing bacteria almost invariably present upon fruits
and vegetables?
12. Why is it necessary to have sound fruits and vegetables for canning?
13. What tale does a bruise on fruit or vegetable tell to one versed in the
elementary facts of bacteriology?
14. Why is intermittent processing at 212° Fahrenheit a surer method of
sterilization than a single processing for a longer time in a water- bath ?
15. What advantage has the product of fractional sterilization over that
produced by a steam retort?
16. Why is it well to can fruit as soon as possible after it has been picked?
17. How can you explain the rapid spoiling of food which has been imper-
fectly sterilized?
18. Describe “ swells.” What is the cause of them? Describe flat sours.”
What is their cause?
19. Why is a large percentage of spoilage in canned goods due to anaerobic
bacilli? By what care can we reduce the danger of that to a minimum ?
20. Why is a leaky can or imperfectly sterilized product extremely dan-
gerous? What substances are formed in the process of putrefaction?
21. Under vdiat conditions are bacteria, yeast, and molds of use in the
preparation of food?
22. What four methods are commonly used in the preservation of foods?
23. Upon what principle is the preservation by drying based? Why are
fruits more easily preserved by drying than are meats, fish, etc.?
24. Name the substances which may be classed as harmless preservatives.
From the attacks of what forms of microorganisms do these protect foods? Explain the preserving power of two of these harmless preservatives.
25. Why should preserving powders be condemned even when their in-
jurious effects cannot be proved?
26. What responsibility has the public in the continuance of the use of
such powders?
27. What is the aim in the preservation of foods by heat?
28. What is meant by pasteurization? By sterilization?
29. Why are foods much more easily sterilized by boiling when there is
present a certain amount of sugar and acid?
30. Why is much care and skill necessary in the preserving of corn, peas,
etc., by heat alone?
31. Why can foods be kept for a certain length of time in cold storage?
BACTERIOLOGY OF CANNING
35
BIBLIOGRAPHY
1. Bitting, A. W., United States Department of Agriculture, Bureau of
Chemistry, “ The Canning of Foods,” Bulletin No. 151, 1912. Super- intendent of Documents, Government Printing Office, Washington, D. C. 10 cents.
2. Bitting, A. W., United States Department of Agriculture, Bureau of
Chemistry, ‘‘ Methods Followed in the Commercial Canning of Foods,” Bulletin No. 196, May, 1915. Superintendent of Documents, Govern- ment Printing Office, Washington, D. C. 10 cents.
3. Buchanan, Estelle D., and Robert Earle, “ Household Bacteriology,”
1913. The Macmillan Company, New York City, N. Y. $2.25.
4. Conn, H. W., “Bacteria, Yeasts, and Molds in the Home,” 1912. Ginn
& Co., New York City, N. Y. $1.
5. Duckwall, Edward Wiley, “ Canning and Preserving of Food Products
with Bacteriological Technique,” 1905. The Pittsburgh Printing Company, Pittsburgh, Pa. $5.
6. Elliott, S. Maria, “ Household Bacteriology,” 1910. American School
of Home Economics, Chicago, 111. $1.50.
7. Jordan, Edwin O., “ Bacteriology,” 1912. W. B. Saunders Company,
Philadelphia, Pa. $3.
8. Lohnis, F., and Smith, N. R., United States Department of Agricub
ture. Journal of Agricultural Research, “Life Cycles of the Bac- teria,” vol. 6, No. 18, 1916. Superintendent of Documents, Govern- ment Printing Office, Washington, D. C. 25 cents.
9. McElroy, K. P., and Bigelow, W. D., United States Department of
Agriculture, Bureau of Chemistry, “ Canned Vegetables,” Bulletin No. 13, part 8, 1893.
10. Van Rensselaer, Martha, Cornell Reading Courses, “ Household Bac-
teriology,” January, 1913. New York State College of Agriculture, Cornell University, Ithaca, N. Y.
11. Wiley, Dr. Harvey W., “Foods and Their Adulteration,” 1911. P.
Blakiston’s Son Company, Philadelphia, Pa. $4.
12. “ Bacteriology of the Household,” in Lippincott’s Home Manual Series
(in preparation). J. B. Lippincott Company, Philadelphia.
CHAPTER III
PREPARATION AND EQUIPMENT
The same general conditions hold for canning indoors or out of doors. Convenient equipment, carefully selected and ar- ranged, surroundings clean and free from dust, and a plentiful supply of water are among the essentials.
INDOOR CANNING
During certain seasons of the year weather conditions make it more comfortable to work indoors. Small quantities of fruit or vegetables can he more conveniently handled in the kitchen than out of doors.
Arrangement of Equipment. — When canning in the kitchen, a part of the work, such as sorting, washing, cutting, and peel- ing, may he done on the porch. Jars may be sterilized and brine and syrup made in the kitchen while the fruit is being prepared on the porch. After cooking, which with vegetables may in- clude blanching and with fruits may involve plumping, the cool- ing and packing may be done on the porch, provided it is screened against bees, wasps, flies, and other insects which are attracted by the odors of the products being canned. The at- tractive odors of the fragrant fruits and spices are alluring to these insects (Fig. 16).
Utensils Used in Preparation. — Only the equipment neces- sary for convenient, accurate, and efficient work should be se- lected. First, it is well to consider the utensils necessary for the washing, peeling, coring, and slicing in the preparation of the fruit and vegetables. For washing, it is best to use small brushes having strong bristles, bowls for the water, and pans for drain- ing. Some good types of knives for paring and peeling, selected with reference to comfortable handling and well-shaped cutting edge, are shown in the illustration. Since coring and slicing of fruit are constantly being carried on in cooking operations the year around, it is worth while to provide these inexpensive uten- 36
PREPARATION AND EQUIPMENT
37
sils, which will also add to the efficiency of these operations in canning. Good types are shown in figure 17.
Fig. 16. — A group of useful utensils for washing, peeling, coring, grating, and slicing fruit
and vegetables.
Fio. 17. — Special equipment necessary to obtain most successful and accurate results.
Successful results largely depend upon the accuracy with which directions are followed. With this idea in view, a small special equipment is suggested. For measuring liquids, the one-
38
SUCCESSFUL CANNING AND PRESERVING
half pint glass cup and enamel or aluminum quart measure will be sufficient. Tin utensils are objectionable because fruits are discolored by them. In securing level measures of dry material the use of a spatula is suggested. It has many other valuable uses. A flat cane paddle used in packing may be substituted for the spatula. Scales are invaluable when undertaking canning in large quantities. The clock must be constantly consulted to in- sure correct time for the various steps in the processes of canning and preserving. The saccharometer is suggested for the purpose of measuring the density of syrups used in canning fruits ; ther-
Fig. 18. — Utensils used in blanching and in cooking.
mometers aid in the jelly-making process, as well as in making jams and marmalades. A fuller description of their use is given in the chapter on ‘ ‘ Preserving. ’ ^ A salt percentage scale is used to determine the density of brine for use in pickling (Pig. 17).
Utensils Used in Cooking and Processing. — The equipment thus far described is useful in preparation of fruits and vege- tables for canning. Next to be considered are utensils for cook- ing and processing. In the blanching necessary for some fruits and vegetables a large vessel for boiling water is necessary. This must be large enough to immerse wire baskets containing the fruit to be blanched. The same pan or tray used later in the pre- serving serves here for transferring the dripping baskets or
PREPARATION AND EQUIPMENT
39
blanching cloth to the cold bath which follows the blanch in many cases. The large preserving kettle illustrated is useful in many ways. It might be used for the blanching vessel, the preserving kettle, and even as the processor. It is economy to have it of the most durable material possible. Two ladles — one cup-like with pouring lip for liquids, and the other flat and perforated for skimming — will be helpful during the cooking as well as when filling the containers (Fig. 18).
Fig. 19. — The processor and rack with jars ready to be sterilized. Note all clamps are raised and screw-top only partly screwed on.
In processing, which is described later, it is necessary to have a tightly covered vessel large enough to sterilize a convenient number of jars at one time. A rack which will raise the con- tainers from the bottom of the sterilizer must be used to allow boiling water to circulate beneath as well as around the con- tainers being sterilized. This rack is most convenient when it is supplied with handles so that all the jars on it may be lifted at one time (Fig. 19). Wire hot- jar lifters will prevent burning fingers (Fig. 20).
Cooperative canning also is a method of minimizing labor (Figs. 21 and 22).
40
SUCCESSFUL CANNING AND PRESERVING
OUTDOOR CANNING
There are many advantages and pleasures in canning out of doors, especially when large quantities of farm products are to be taken care of in the shortest possible time. Outdoor canning gives opportunity for cooperative work among clubs and neigh- bors. In cooperative canning the minimum amount of labor, if well organized, will give larger and better results. This work has stimulated many women and girls to spend more time in the open and bring other tasks out of doors. Choose a shady, green, cool spot convenient to the water supply for the canning. The fact has been mentioned before that insects are attracted by odors from the fruit being canned, and it might be well to consider baiting fly-traps near where the canning is done (Fig.
Fig. 20. — Tongs for handling hot cans.
23). Flies prefer nitrogenous food to sweets, and if the traps are properly baited with milk clabber or meat they will be less attracted to the products being canned (Figs. 23 and 24). In addition to the equipment already described above under ‘ Tn- door Canning,” there are important matters of special concern in outdoor canning..
Arrangement of Tables. — Tables of the proper height should be conveniently arranged for different steps of the work. The diagram shown offers a suggestion for placing of tables with reference to the canner, especially when canning in tin (Fig. 25).
Table 1 is equipped for the sorting, washing, blanching, peel- ing, and coring. It should be as few steps as possible from the canner, to save time and labor in the blanching process.
Table 2 should be placed near Table 1, because the fruit is passed to this table for packing, weighing, and adding of brine or syrup.
Table 3, which is for capping and tipping and should stand evel, should be near the canner, because of the numerous trips
Fig. 21. — Cooperative canning minimizes labor; canning club girls in Anson County, North Carolina, at work.
PREPAEATION AND EQUIPMENT
41
Fig. 22. — North Carolina county agents at Peace Institute, Raleigh, N. C.
PREPARATION AND EQUIPMENT
43
to be made between them. Table 3 might be omitted if one is canning in glass only. Illustrations show other convenient ar- rangements of tables for out-of-door canning (Figs. 26 and 27).
When tin cans are used it necessitates the use of tipping cop- per and capping steel. Sometimes the same fire which heats the water in the canner is used to heat these tools. A little oil stove which burns a gas flame is certainly worth having for heating the tools. It gives a hotter and cleaner fire than the wood fire in the canner; it heats the. steel more quickly and saves cleaning and retinning the tools so often (Figs. 28 and 29).
A portable canner is a necessary convenience for out- of-door canning. This may either be homemade or pur- chased. There are a number of portable canners at reason- able prices on the market at present. Considering the fact that most concerns furnish tipping copper, capping steel, and blanching trays with the outfit, it is cheaper to buy one complete than to attempt to build one and purchase a set of tools. The essential 23 —a homemade fly-trap,
feature of such a canner is a good, large fire-box, above which is a compartment for heating water. In the water compart- ment are placed two or three wire baskets for handling a quantity of fruit at one time in blanching or a number of jars or cans in processing. A wooden rack placed below these baskets raises them above the fire-box and allows circulation of the water around jars and prevents breaking during the processing. For this tank there must be a close-fitting cover (Fig. 30).
A large tub of cold water for cooling tins should be placed beside the canner. When canning in glass out of doors, a cloth should be provided to place over the jars immediately after re-
44
SUCCESSFUL CANNING AND PRESERVING
moving them from processing, to prevent the cold breeze from striking the glass and breaking it.
SELECTING CONTAINERS
Types of Containers. — The type of container is very impor- tant and should be considered when the first equipment for can-
Fig. 24. — Mississippi club girls building a fly-trap for out-of-door canning.
ning is secured. The most essential feature to consider is a perfect closure ; then the size and shape desired for different products.
Tin Cans. — AVhen canning is to be done in tin and the buying is to be direct from the manufacturer, it is very necessary to order
PREPARATION AND EQUIPMENT
45
the cans as early as possible to take advantage of the lower prices offered before July 1. Many firms close their factories after this date, and will not consider any order in less than carload lots. The same thing is true in some of the glass factories. If you anticipate canning in large quantities, make an estimate for your dealer or order early from the manufacturer. Tin cans are designated by number rather than by the measure of liquid they carry, as is the case in glass containers (Fig. 31). Flat
No. 1 cans are the smallest that are advisable for use in home canning, and their use is very limited. The No. 1 fiat or squat can is more attractive than the tall No. 1 for the most of the prod- ucts packed in so small a tin, and is especially desirable for such packs as sweet Spanish pimientos, figs, tomato paste, etc. The No. 2 tin can is the size most generally used for canned vege- tables and small frqits. Corn and peas are more easily sterilized in this sized tin, and for that reason these products should not be packed in any larger container. No. 3 can is used more often in some localities than No. 2, especially for canning peaches, tomatoes, pears, etc. (Fig. 32).
Fig. 25. — A convenient arrangement for out-of-door canning.
46
SUCCESSFUL CANNING AND PRESERVING
Fig. 26. — Canning out of doors, State Normal School, Harrisonburg, Va.
PREPARATION AND EQUIPMENT
47
Fig. 27. — Canning tomatoes from the scholarship plot, State Normal School, Harrisonburg, Va.
Fig. 28. — A kerosene stove which burns a gas flame for heating soldering tools.
48
SUCCESSFUL CANNING AND PRESERVING
The enamel-lined can is necessary when canning berries, plums, cherries, beets, pumpkin, and hominy, which may not be packed in the ordinary tin cans, because they are affected by the tin in such a way as to rapidly lose their color and flavor. Figs also will keep a brighter color when packed in these enamel-lined
cans. When enamel-lined cans cannot be secured, these prod-- ucts should be packed in glass.
A No. 10 can is sometimes used for tomatoes and spinach, but in such a large container a great deal longer time is re- quired to sterilize food; there- fore it is better suited for hotel and institution canning. It is not generally advisable to pack in No. 10 cans unless process- ing is done under steam pres- sure. Sometimes fruits are packed in these containers in a thin syrup during the very busy season, then opened, cooked more, and repacked in marketable containers during the less busy season, as the orders come in. This is not practicable, however, unless a
for heating tools. A gasoUne fire-pot or“ehar! large quantity of ripening
fruit must be taken care of in a very short while, and time cannot be allowed for plumping and careful packing. Often semi-tropical fruits are handled in this manner in the orchards and shipped to the large packing-houses, where they are repacked in smaller commercial containers be- fore marketing.
The square tin cans are sometimes used for asparagus tips. In California such a container is more generally used for this product than the round can.
Fig. 29. — A fire-pot burning A gasoline j coal bucket may also be used.
PREPARATION AND EQUIPMENT
49
The cans described above are those which can be secured with solder hemmed caps.
''Sanitary” Cans. — The so-called ''sanitary” cans are widely
Fig. 30. — A folding portable canner.
Fig. 31. — Standard sizes of tin containers.
used by commercial packers. They require a machine for seal- ing. A small hand machine for sealing special sanitary cans is illustrated here (Fig. 33). The cans with the proper closure
50
SUCCESSFUL CANNING AND PRESERVING
to use in this machine are a little more expensive, perhaps, than the regular cans in stock, but the time and material saved by this process more than cover the extra charge. This method
10
6 3/76
Capacity
UGJoz.
|
2 |
“ ZVl6 |
|
|
Capacity EZ.Zoz. |
||
|
/ |
3V4 |
|
|
Capacity' IZ oz. |
r\5 |
Fig. 32. — Size of cans used for household purposes.
eliminates the use of solder and canning flux in the sealing of cans. If machinery cannot be employed hand tools will be necessary (Fig. 34). It is necessary to designate the size when
PREPARATION AND EQUIPMENT
51
ordering cans, since the diameter of the opening should cor- respond with that of the capping steel to be used. There are two sized openings, 2Yj(,-inch and 2'/^p-inch. Cans with the
Fig. 33. — Hand machine for sealing special sanitary cans. (Courtesy of Bowers Can Seal Company, Boston, Mass.)
2Yig-inch opening are more generally used. The solder hemmed caps are preferable, because they save solder and time in put- ting them on. Plain tia caps are not worth coRsidering.
52
SUCCESSFUL CANNING AND PRESERVING
Glass containers are more varied in sizes and shapes than the tin and lend more opportunity for displaying a variety of at- tractively packed products, both for the home pantry and for market. Throughout this book suggestions are made from time to time about salable products in commercial packages. This is for the purpose of encouraging the canning, preserving, and
Fig. 34. — Capping steel and tipping copper.
selling of surplus products. The highest quality of commercial products on the market should tend to stimulate ideals and standards (Fig. 35). These jars can be obtained in one-half pint, pint, quart, and one-half gallon sizes.
Selection of Jars. — ^Jars should be selected with reference to suitable size and shape for the product to be packed, keeping in mind economy in the initial purchase and durability. Other
PKEPARATION AND EQUIPMENT
53
important considerations are beauty of proportion, tint and quality of glass. Not only are these qualities considered by those who are packing for high-class sales, but also by the house- wife who enjoys artistic expression through arrangement and preservation of beautiful form and color in skilful packing. The square jar is effective for showing cjuality and pack.
Lightning Seal. — The wide-mouth glass-top jar with wire clamp which is attached to the neck of the jar is a satisfactory one. A jar with this closure is known as one with a ^‘lightning seal.” This seal is made by different manufacturers and put on the market under various trade names. A jar with this closure is
Tig. 35. — A group of jars for household use.
an easy one to handle w^hile the jar is still hot. Immediately after processing and sterilizing it is necessary only to push down the lower clamp around the neck of the jar. This gives the amount of pressure necessary to assist in the sealing of the jar as it cools. The rubber used is placed in the groove of the neck of the jar, and the cap fits down on the top of the rubber, which prevents the bottom of the glass top from coming in direct contact with the top of the jar. It is the rubber that makes possible this seal by adhering to both the top and the jar. Ever\'- thing must be very hot to obtain a good seal, and for this reason directions are often given for cooking the fruit in the jar. This heating drives out some of the air, forming a partial vacuum in the jar. At this point the clamp is pushed down, preventing entrance of air as the jar cools. The jar is then
54
SUCCESSFUL CANNING AND PRESERVING
sealed by the pressure of air on the outside. Sometimes a jar of this type is spoken of as a ‘ ‘ self -sealing ” jar. This sort of seal- ing has great advantage over the old screw-top jars.
Screw-top jars which demand handling while hot are difficult to screw on tightly enough to insure good sealing. If the tops
are screwed down by hand, the wrists become tired and cramped before many are sealed, and it is uncertain whether all are suffi- ciently tight. There is a simple tool on the market for screw- ing on tops.
The zinc top should not be used, because fruits and vegetables which contain acids are unfit to eat after contact with the zinc cap. New tops should be secured for all jars of this type. The glass used in this type jar is usually tinted. While the fruit will be easily kept in this glass, it gives the fruit an
PREPARATION AND EQUIPMENT
55
unnatural appearance, and it is not so attractive. When pack- ing fresh fruit and vegetables for sale, the fair natural color en- hances the value of the finished product.
Safety-valve Seal. — The jar with the safety-valve seal is beautiful. It is made of clear flint glass, and the seal is the same principle as the lightning seal. While being processed the lid is held in place by a wide black clamp which may be re-
pagne shaped ketchup bottle. C. Pint square jar.
moved when the jar is cold and sealed. It then presents a very attractive appearance. Jars of this type are more expensive than the other types mentioned. They are often used by select preserving kitchens that furnish goods for high-class, fancy trade (Figs. 36, 37 and 38).
The Hermetic^’ Jar. — The hermetical sealing jar with the gold lacquered cap and wire clamp is used more often for com-
56
SUCCESSFUL CANNING AKD PRESERVING
mercial purposes, though there are some household jars of this type on the market. The cap is said to be washed in a gold lacquer that will not be affected by vegetable or fruit acids coming in contact with it. Around the inside edge of the cap a gasket or rim of sealing composition fills the space between the cap and jar, and this softens when heated and adheres to the jar. The sealing of this jar is practically the same as the light- ning seal jar. Heating forces out the air and forms a partial vacuum in the jar; then the wire clamp, which should he
Fig. 38. — Individual containers: A. 4-ounce vase-shaped jar, hermetic cap. B. Straight- sided 4-ounce jar, hermetic cap.
placed on the jar at the beginning of the process, furnishes sufficient pressure to prevent cold air from rushing into the jar as it cools. It is the pressure of the outside air, nearly sixteen pounds to the square inch, which keeps the jar sealed. Com- mercial products are often packed in jars with this type seal. Because the sealing composition is under the edge of the cap and not exposed, it is not so liable to become punctured by mice and roaches nibbling it, as is sometimes the case where rubbers are used.
Buhber rings dry and deteriorate with age. They become porous and sometimes crack. When this happens, the air gets
PREPARATION AND EQUIPMENT
57
in and, because the partial vacuum is broken, the seal is no longer good and the product will spoil. A perfect seal, where the rubber ring is exposed, will hold only so long as the life of the rubber lasts. In selecting rubber rings it is wise to secure the best and always use new ones. The price of a dozen rings is less than the value of the contents of one jar, so it is economy to have new rubbers each year. The thick, red and gray rubber rings are among the best. The black one is better than the
Fig. 39. — Box of rubbers and a jar.
white, because the chemicals used to bleach this kind cause it to dry, crumble, and crack in less time than the better-grade rubber (Fig. 39).
QUESTIONS
1. Describe the care necessary to protect the food from insects wliile work- ing on the porch or under the trees.
•2. When considering a piece of equipment, what would determine its selection ?
3. What principles are involved in the arrangement of tables in Fig. 10?
4. State, in the order of their importance, the' features to be considered in
the selection of containers.
.5. Why are plain tin containers unsatisfactory for some fruits and vege- tables? What kind of containers would you use for these foods? When is glass ])referable to any other?
6. Descril>e the principle of the so-called “ lightning seal.”
7. When a rubber ring is used in the seal, wiiich kind would you select and
why should it be renewed every year?
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SUCCESSFUL CANNING AND PRESERVING
BIBLIOGRAPHY
1. Bitting, A. W. and K. G., “ Canning and How to Use Canned Foods,”
1916. The National Canners’ Association, Washington, D. C. 30 cents.
2. Breazeale, J. F., United States Department of Agriculture, Farmers’
Bulletin 359, “ Canning Vegetables in the Home,” 1910. Secretary of Agriculture, Washington, D. C.
3. Breazeale, J. F., United States Department of Agriculture, Farmers’
Bulletin 521, “ Canning Tomatoes at Home and in Club Work,” 1913. Secretary of Agriculture, Washington, D. C.
4. Gould, H. P., and Fletcher, W. F., United States Department of Agri-
culture, Farmers’ Bulletin 426, ‘‘ Canning Peaches on the Farm,” 1910. Superintendent of Documents, Government Printing Office, Washington, D. C. 5 cents.
5. McDonald, May C., and Stanley, Louise, University of Missouri, “ The
Preservation of Food in the Home,” vol. 15, No. 7, Extension Series 6, March, 1914. University of Missouri, Columbia, Mo.
6. Rose, Flora, Cornell Reading Courses, “ The Preservation of Food
in the Home,” 1912, parts 1, 2, and 3. New York State College of Agriculture, Cornell University, Ithaca, N. Y.
7. Shaw, S. B., North Carolina Department of Agriculture, “ The Home
Canning of Fruits and Vegetables.” North Carolina Department of Agriculture, Raleigh, N. C.
8. United States Department of Agriculture, States Relations Service,
Office of Extension Work in the South: A-81, ‘‘Canning, Preserving, and Pickling”; 782, “Peppers”; 775, “Use of Vegetables from Win- ter Garden.” Office of Extension Work in the South, States Relations Service, Department of Agriculture, Washington, D. C.
CHAPTER IV
CANNING IN TIN
Since canning in tin is becoming much more widely used in the household, it may well be presented first. On the farm, for instance, where there is a large yield of fruit or vegetables to be canned, the canning process in tin can be handled with more speed, less danger of breakage, and at a very much smaller initial cost. For all these reasons, in many localities the canning in tin is preferred.
Preparation for Canning in Tin. — Special equipment for canning in tin should be assembled early in the season, as prices are better then and there may be difficulty later in securing certain supplies, as already suggested. The cans should be ordered early and the processing vessel, whether it be a com- mercial canner or one made at home, should be installed some time before the actual canning is to begin. When the canner is decided upon and the solder hemmed caps and cans ordered, the next to consider is the tipping copper, capping steel, and a file. To clean these tools, a canning flux should be made and some powdered sal ammoniac placed in a can to rub the tools with after heating.
Making Flux. — Put some commercial hydrochloric (muri- atic) acid in a glass or crockery vessel (not metal), add strips of sheet zinc until no more can be dissolved. To this add an equal quantity of water. Label this “Flux’" and use carefully. Very little must be used, and care must be had not to allow any of it to enter the can, as it will injure the contents. The use of flux is described under “Capping.” When canning, have one vessel (a can will do) with enough flux in it to clean the tools. Keep separately, in a glass bottle, the quantity to be used in sealing cans.
Cleaning and Tinning the Steel and Copper. — It is of first importance to have capping steel and tipping copper in good
59
SUCCESSFUL CAXNIXG AXD PRESERVIXG
GO
condition. In case they are msty, they may have to be filed. Otherwise, rubbing them with coarse sand-paper or on a brick will smooth them. Care must be taken to keep the edge of the capping steel true if the file is used. Both the tipping copper and capping steel must be kept tinned or coated with solder to make the solder flow evenly when sealing the cans. Place a handful of sal ammoniac mixed with a few pieces, of solder (one- half cupful of sal ammoniac and three inches wire solder) into an old can. This proportion will be sufficient for retinning the tools one time. The sal ammoniac can be used again if more solder is added. Heat the already smooth tipping copper and capping steel until almost red hot, dip into the flux, then into the sal ammoniac and solder, turning them about and rubbing them until bright and well coated with solder; then dip into the flux again. The best sealing can be done with the least effort if the tools are kept in a clean, bright condition.
Plenty of clean white cloths should be at hand during the can- ning process. There should be wire lifters for handling hot cans and blanching trays. Sufficient wood should be piled near the canner for keeping up the fire. A tub of cold water for cooling the tins as soon as they are removed from the processor should be at one side of the canner, and there should be a water supply near at hand, because it will be necessary to change the water from time to time in order to have a cool supply. The equipment should be placed, if possible, where it can be used for the entire season.
Having outlined a convenient arrangement of this equip- ment, the various steps in the process of canning in tin may next be considered.
STEPS TAKEN IN CANNING IN TIN
1. Selection of good sound fruit and vegetables is of para- mount importance. Unless the product to be canned is of the highest grade and in prime condition, it is useless to hope that special care and skilful packing will result in anything more than disappointment and failure. In securing fine quality, much depends upon having the vegetable or fruit absolutely fresh.
CANNING IN TIN
61
crisp, and clean, and kept cool. All steps, from beginning to end, of any lot of canning should be carried tlirough as rapidly as possible. A good slogan is, One hour from the field to the can.’^
2. Sorting and grading should be done verj" carefully, ac- cording to the size and degree of maturity and ripeness. Use only uniformly well-ripened products (Figs. 40 and 41). Dis- card all defective ones, and use together those of the same size. In canning, the flavor is retained only when young, tender.
Fig. 40. — Sorting and grading tomatoes.
quickly grown vegetables are used. Commercial concerns some- times have what they call grading paddles. They consist of a flat board vdth holes, which correspond to the opening in the glass jar in size. Peaches, for instance, which are too small are set aside to be packed as sliced peaches or for sweet pickles, and the ones which are too large are kept together, while all that slip through easily are made up together in one batch. This grading before cooking simplifles sorting when packing', saves much time, and gives a more uniform product throughout.
3. Scalding, Peeling, and Coring. — Some fruits, such as peaches and tomatoes, are scalded in order to peel them smoothly.
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SUCCESSFUL CANNING AND PRESERVING
Put fruit or vegetables to be scalded into trays or squares of cheesecloth and lower into boiling water for one minute (Fig. 42). Kemove at once to prevent cooking. Plunge into cold water, which prevents softening of the fruit and causes it to shrink, making the skin more easily peeled from the flesh. When the skin does not come off clean without tearing bits of flesh, it is an indication that the scalding has not been successful. This may be due to having the fruit too green, to overcooking, or to adding a large quantity of fruit at one time, which too
Fig. 41. — Uniform tomatoes together.
quickly cooled the water. A slender-pointed knife is useful for peeling and coring.
4. Blanching consists of plunging the vegetable or fruit into a large amount of boiling water for a short time. A wire basket or square of cheesecloth serves for handling large quan- tities of fruit at one time. The blanch gives a more thorough cleaning, because the scalding water tends to remove the bacteria from the surface of the fruit or vegetable. It also improves the flavor and removes strong odor and flavor from certain kinds of vegetables. The fruit shrinks in the blanch and becomes more flexible. A full pack is then more easily made. The time re-
CANNING IN TIN
63
quired for blanching varies with the state of maturity of the different fruits and vegetables. Blanching peaches and pears gives them a more transparent appearance, better texture, and mellow flavor. Using it for cherries will prevent splitting and cracking. Spraying fruit with cold water after blanching will make it finer. Sometimes it is well to drop the vegetable into a
cold salt-bath for an instant after the blanching to make it more crisp. In the case of green beans, peas, and okra, such a cold salt dip may help to keep the green color.
5. Sterilizing containers is very essential before packing them. This may be done while the fruit is being sorted. Wash the cans and drop into boiling water for ten to fifteen minutes. On removing them from the water, turn open ends down on a
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SUCCESSFUL CANNING AND PRESERVING
clean towel to keep out dust and air. If stacking them, turn open ends of two cans together.
6. Packing. — The can should be filled as full as possible with- out crushing pieces. There should be no space which would allow the pieces to move about and bruise and break one another. In general, when packing in tin for the market, it is well to do sufficient weighing to insure minimum weights from falling below the standard chosen. Federal and most state laws require that cans be filled as full of food as is practicable for processing, and that they contain only enough liquor to fill the space and cover the contents. Plan in advance and work rapidly. Do not allow filled cans to stand before adding liquid and exhausting, because to do so will injure the product. Add seasoning and mark the cans with pencil or knife to show contents.
7. Adding Water, Brine, or Syrup. — Add the liquid to within one-fourth of an inch of the top. Shake the can and tap gently on the table to dispel air within the can. Now clean and wipe the groove around the opening and slip on the solder hemmed cap (Fig. 43).
8. Capping. — ^Use a small brush, cord, or little mop, made by tying a clean white cloth around the end of a small stick for applying the fiux around the groove, being very careful to allow none of it to enter the can. The fiux is used to make the solder adhere to the tin. Apply the clean, hot capping steel, holding the cap firmly in place with the center rod while lower- ing the steel. Turn the steel steadily until the solder flows: a half turn forward, a half turn back, with a sudden twist forward again to swing the melted solder around the groove evenly while lifting the steel. Hold the center rod firmly until the solder cools, making a perfect seal.
9. Exhausting. — Place the cans in trays and lower into boil- ing water to within one inch of the top to drive the air out of the cans. Let them stay the shortest time possible to drive out the air. Dense foods like corn and sweet potatoes require a longer time for exhausting than products which are more juicy. The denser foods are poorer conductors of heat, and it takes a longer time for the contents in the center of the can to become
CANNING IN TIN
65
heated. Ordinarily three minutes is long enough for exhausting cans not larger than No. 3. Exhausting is necessary. If omitted, the air left in the can expands, causing it to bulge. The can may not resume normal shape, or, if it does and is exposed to
Fig. 43. — Capping Fig. 44. — Tipping.
a waiTQer temperature, it may again expand, giving the appear- ance of a ‘‘swell.’’ Future orders may be cut off because of a single can like this. The presence of air in the can may cause the tin to dissolve more rapidly and enter into the food.
10. Tipping. — Immediately after exhausting, close the small 5 .
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SUCCESSFUL CANNING AND PRESERVING
hole at the top of the can. Dry the cap, apply flux as for capping, and nse a little wire solder (Fig. 44). Hold the hot tipping copper in the right hand, placing the point over the hole, and barely touch the solder to it. Bring the hot copper ver- tically over the hole and lift it so that only a bead will drop and make a neat, round tip.
11. Processing is heating to sterilize the contents of the cans, which have been packed, exhausted, and tipped. In a hot-water canner, the water should be boiling vigorously when the cans go in. Lower the can slowly under the water and watch for a shower of bubbles. If the bubbles are seen, this shows that there
is a leak at the point from which the bubbles come, and the can must be taken out and resoldered. Account should be taken of the time beginning when the water first boils after emerging 'from the cans. Keep it boiling continually. When processing in a steam-pressure canner, begin counting time when the gauge denotes the amount of pressure you wish to use in processing. In intermittent processing, the vegetable is processed for forty- five to sixty minutes at boiling temperature on each of three successive days. The time is sometimes reduced to two days with very young, fresh string beans and other more easily sterilized vegetables.
CANNING IN TIN
67
68
SUCCESSFUL CANNING AND PRESERVING
12. Cooling. — Cool all products in tin as quickly as possible after processing to stop the cooking. Overcooking breaks down the texture of fruit and injures the flavor and color. Plunge cans into very cold water immediately, especially when process- ing inteimittently. Never stack cans together until entirely cold. The cans should be dried before storing to prevent rust- ing. This may be done by either drying them with a cloth or standing, them in the sun after the plunge in cold water.
13. Test for Defects. — Tap the top of the can with a metal, and if the containers are sealed a clear, ringing sound is noticed. If the seal is imperfect a dull sound will be heard. It is a common sight in factories to see a workman beating a rapid
tattoo on the ends of cans with a metal. He can detect by the variation in sound or a single blow when all is not right (Figs. 45 and 46) .
14. Labelling. — Cans should never be labelled until perfectly cold (Fig. 47). It is better to wait five or ten days so as to be sure that they are all sound. If products are to be sold, they should be freshly labelled just before shipping and have the net weight stated in pounds and ounces, with packer’s name and address on each can. Place the sealed end down so the smooth end wdll appear at the top when standing on the shelf. The paste used should be placed only on the label at the end, so that no paste will touch the tin. It may cause rust if the paste touches the can.
CANNING IN TIN
69
Paste :
1 cupful of flour 1 cupful of cold water
1 teaspoonful of powdered alum Vj teaspoonful of oil of cloves
3 cupfuls of boiling water
Mix the flour and one cup of cold water thoroughly. Add the boiling water and bring slowly to the boiling-point, beating all the while to prevent lumps. Boil for five minutes. When cooked, add the alum and oil of cloves, pour into glasses with covers. This will keep for some time and make an excellent paste for use in labelling cans and jars.
Frequently the outside of the cans is lacquered before label- ling to prevent rusting. In damp climates, where cans rust easily, this is advisable. An attractive label will add a great deal to the appearance of the finished product, and it should be chosen carefully with this idea in view.
Any one wishing to can for the market should look up the state laws and requirements about the matter. It is not so neces- sary to be familiar with the Federal laws unless interstate ship- ments are to be made. Detailed information on state laws and regulations may be obtained by writing to the State Food Com- missioner, State Board of Agriculture, and Federal rules and laws can be secured from the Bureau of Chemistry, U. S. Depart- ment of Agriculture, Washington, D. C. Write for the publica- tions and state what products are being packed for sale.
This information is given for the benefit of those who are canning for commercial purposes; every one who cans for the market should be encouraged to know the food laws. Such things sound more serious than they are, and one should not be over- whelmed with the seemingly endless details attached to the can- ning business. New facts pertaining to food conservation are being published constantly, and those who are interested in the various phases of the subject should keep informed by securing from their State Board of Agriculture, the U. S. Department of Agriculture, and tlhe National Canners’ Association, from time to time, all publications and reports.
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SUCCESSFUL CANNING AND PRESERVING
QUESTIONS
1. What is the meaning of efficiency in canning?
2. Describe the equipment needed and its arrangement when preparing to
can in tin.
3. How is ‘‘ flux ” made ? For what is it used ?
4. What is your standard for the external appearance of a tin of fruit or
vegetable? What steps are necessary to secure this standard?
5. Describe how to coat with solder the tipping copper and the capping
steel.
6. When such a tin has been opened, what standard should the contents
equal? What steps are necessary to secure this standard?
BIBLIOGRAPHY See end of Chapter VI, page 86.
CHAPTER V
CANNING IN GLASS
Canning in glass is very similar to canning in tin. The same principles hold good throughout. The initial cost of con- tainers is greater than when canning in tin, but for home use it is more economical, because glass is used year after year, while tin should be used only a single time.
The first four steps under ‘‘Canning in Tin” are also to be followed when packing in glass (see p. 60) ; the additional steps are given below. Convenient arrangement of all equipment is very essential before undertaking the work.
5. Sterilizing. — Jars should be washed and placed, side down, in a vessel and covered with cold water. The water should be slowly brought to a boil and allowed to boil for fifteen minutes (Fig. 48).
6. Packing. — After selecting and sorting the fruit or vege- table for uniformity in ripeness and size, and after blanching it, the fruit should be arranged in the jar with reference to sym- metry and the best use of the space within the container. In placing the fruit or vegetables into a jar, a thin, flexible paddle or spatula, made out of cane or soft white wood, is useful. It is important to have a good, clear syrup. Clear, soft, or distilled water should be used. Sometimes better results could be ob- tained if the quantity of water used for making the syrup could be first boiled, strained, and cooled before using. Mix the sugar and water by stirring as it heats, to be certain the syrup is uniform (Figs. 49, 50, and 52) .
7. Paddling. — A more slender paddle is used for taking bubbles of air out after the liquid has been added. This is done by running the paddle down the side of the jar and touching the bubble with the rounded end of the paddle. The air creeps up the paddle to escape and is displaced by the liquid. More liquid should be added after paddling in order to have the jar
71
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SUCCESSFUL CANNING AND PRESERVING
full to overflowing. These paddles can easily be made at home (Fig. 51). Bamboo cane is suitable material for making them;
Fig. 49. — Packing uniform pieces of rhubarb.
an old Ashing pole will do. Split the cane, cut the paddle nine to twelve inches long, leaving a joint at the top for a handle.
CANNING IN GLASS
73
Fig. 50. — Well-packed jar of peaches.
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SUCCESSFUL CANNING AND PRESERVING
Whittle the other end until flat, thin, and flexible. Then sand- paper. If green bamboo cane is used, place in the sun to dry after making the paddle.
8. Adjusting the Rubber and Cap. — Be sure the rubber is carefully flattened in its groove and no particle of fruit or seed is present on it before placing on the cap. When a glass-top jar with wire clamp is used, place the lid on evenly and raise both clamps up, the upper one fastened to hold the lid in place.
When a screw-top jar is used, screw the ^ cap evenly about half way. With a her- metic jar no rubber ring is necessary; simply fasten the cap in place on the jar with the clamp. The hermetic jar is self-sealing as it cools, and does not need to have any adjusting of the cap or clamp after processing, as is the case with each of the other above-named jars ; simply leave the clamp in place until the jar is entirely cold.
9. Processing. — Place the jars on a wooden, galvanized, or wire rack to hold them off the bottom of the processor, which is directly over the Are. Sometimes a cloth is put in the bottom of the vessel before placing jars, but this is not a good practice, since the weight of the jars presses the cloth against the bottom of the processor and often causes it to stick and burn. A rack which holds the jars up an inch or two off the bottom is better. In a hot-water canner the water around the jars should be of the same temperature as the contents of the jar to prevent them from cracking, and the water should come within two inches of the tops of the jars. Have a tight cover for the vessel to keep in the steam. Do not count time until the water begins to boil. Keep it boiling steadily for the time required. Seal the jars air-tight promptly at the end of the processing, and remove them from the bath, being extremely careful not to allow a cold
Fig. 51. — Paddles: a. Packing paddle, b. Syrup paddle.
Fig. 52. — Canning in glass on campus of Peabody College for Teachers, Nashville, Tenn.
CANNING IN GLASS
75
76
SUCCESSFUL CANNING AND PRESERVING
draught to strike them. In intermittent processing raise the clamp of the jar at the beginning of each processing to allow for expansion. Seal at the close of each processing. The hermetic jar is not a suitable one for intermittent processing. Processing in glass in a steam-pressure canner is described in a later chapter, '‘Processing at High Temperatures” (see p. 87) .
10. Labelling. — Each jar should be washed and polished before labelling. Here again the choice of the label should be made carefully. One just large enough to have printed the necessary requirements is sufficient. Choose a neat label: white is preferable, with plain, simple black printing. A fancy colored label may not be in harmony with the color of the contents of the jar and will detract from the attractiveness of the product. Place the label on the plain side of the jar, mid- way between the seams and one-quarter inch from the lower edge. When labelling products to be sold, the name of the contents, name and address of the packer, and net weight in pounds and ounces must be stated.
Storing Canned Products. — Store the canned products in a. cool, dry, dark place. Light will cause the color of the products in glass to fade, while products in tin are, of course, not affected by light.
QUESTIONS
1. Give in outline form and in order the steps necessary when canning in
glass.
2. What steps in this process differ from the steps in canning in tin? To
what are the differences due?
3. Which container is more economical for home use? Why is this true?
4. State definitely the principles vdiich are the basis for all kinds of can-
ning.
BIBLIOGRAPHY
See end of Chapter VI, pages 83 and 86.
CHAPTER VI
PROCESSING— HOT-WATER BATH
Processing is the term applied to the operation of sterilizing or heating to destroy bacteria so that the canned goods will keep.
All fruits and juicy vegetables are better in color and texture if sterilized at or near the boiling-point (212° Fahren- heit). For this purpose the hot-water bath is commonly used. Sometimes these oufits can easily be made at home, according to the amount of canning which is to be done.
Homemade Canners. — If only a few jars or cans are to be processed at a time, then flat-bottom vessels, such as a wash- boiler, ham boiler, preserving kettle, or bucket deep enough to permit of being covered after the jars or cans are placed on the false bottom inside, will serv^e the purpose (Fig. 53). When any of these utensils are used it is necessary to have a false bottom on which to set the jars or cans while processing. Narrow strips of wood or wire netting made of medium-sized galvanized iron may be used for this rack. The vessel should be equipped with a tight cover, preferably tin, which is kept in place while the sterilizing is being done (Fig. 54). Such small outfits are intended for use on an ordinain^ cook stove or range.
A homemade canner for use out of doors, where larger quan- tities can be handled, may be made out of tubs or fifty-pound lard cans. Heat for these canners is furnished by portable stoves, or by furnaces made of brick or stone (Figs. 55 and 56) .
Commercial Outfits. — The purchase of an expensive or especially made outfit in which to do the cooking is not necessary. There are, however, a number of inexpensive commercial out- fits which give very satisfactory results. Some of these canners are well built and excellent work can be done, both for com- mercial purposes and for home use. These outfits range in size from those having a four-can capacity to those having a capacity of a few hundred cans. The price varies according to size of the canner and the number of tools and accessories included in the outfit.
77
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SUCCESSFUL CANNING AND PRESERVING
Fig. 53. — An ordinary bucket used as a processor.
Fig. 54. — A wash-boiler with false bottom makes a convenient processor.
PROCESSING— HOT-WATER BATH
79
Manufacturers furnish catalogues having full descriptions and price-lists of these various outfits, and in order to secure a canner best suited to conditions a study of different catalogues will help to make the decision. The requisites of a good com- mercial hot-water outfit may be enumerated thus: First, good quality of material used and of workmanship in the construc- tion ; next, the convenience and cost of operation, in order that
Fig. 55. — Canner made of tubs for outdoor use.
the best results can be obtained with the least possible ex- penditure of time, labor, and fuel.
Equipment Accompanying the Purchased Canner. — The usual portable canner for out-of-door use consists of the following :
Canner Fire-box Return flue Water tank Trays or wire baskets Chimney Tight cover
Accessories Tipping copper Capping steel Can tongs Tray lifters Fluxing brush Charcoal bucket or Fire-pot for heating tools
Materials
Bundle of wire solder Powdered sal ammoniac Bottle of flux Coarse sand-paper or
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SUCCESSFUL CANNING AND PRESERVING
Some canners are round and some rectangular in shape. The lower section or fire-box has a small opening in the door through which the soldering tools may he placed for heating. The water in the upper section will heat more quickly if a smoke passage
is placed in such a way that the water chamber is heated from the smoke passage as well as from the fire-box. Sometimes the chimney is attached at the front of the eanner near the fire-box door ; this necessitates the smoke returning from the outlet at the other end of the fire-box hack to the chimney, and, if the water chamber extends down be- tween the smoke passage and the fire-box, the extra heat ob- tained in this way will cause the water to boil more quickly, thus saving time and fuel. The bas- kets or trays for holding the cans in the eanner are made of gal- vanized metal, with a wire bot- tom and wire handles. This bas- ket serves as a false bottom and fits into the water tank, resting slightly above the top of the fire- box and smoke passages. A wooden rack should be placed be- low this basket when canning in glass so that the bottom of the metal tray will not rest directly on the fire-box. A basket full of cans may be lifted out with wire tongs. The top of the eanner is fitted with a tight cover, which keeps in the heat (Fig. 57) .
Canners should have water in the upper section before a fire is built; if this is neglected with the type of eanner which is
Fig. 56. — A homemade eanner with brick fire-box and tub.
PROCESSJXG— llO r-WATEK BATH
81
Fig. 57^Showing construction of a hot-water canner. (Phillips & Buttorfif, Nashville, Tenn.)
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SUCCESSFUL CANNING AND PRESERVING
Fig. 59. — A folding two-burner gasoline stove. (W. J, Baker Co., Newport, Ky.)
too short is most objectionable to those who are canning (Fig. 57) .
For Heating the Tools. — The tools may be heated in the fire-box of the canner, bnt the suggested fire-pot, charcoal bucket, or gas-flame stove is better for this purpose, since the tools heat more quickly and do not have to be cleaned so often (Fig. 58) . An
Fig. 60. — Tank fitting inside.
Fig. 58. — A kerosene stove burning a gas flame. (Globe Gas Light Company, Boston, Mass.)
soldered together, the solder will melt and the water will leak out, making the canner useless until it is mended.
The chimney should be tall enough to provide a good draught and to carry the smoke away. The smoke from a pipe which is
PROCESSING— HOT-WATER BATH
83
ordinary bucket with a hole cut out of one side near the bottom will make a good substitute for a fire-pot if charcoal or corn- cobs are burned in it. Care must be taken to have the fuel burned to a bed of glowing coals before attempting to heat the tools. This is necessary to keep the copper and steel smooth and clean (Figs. 58, 59 and 60).
A Time-table for Use in Canning Fruits and Vegetables When the Hot- water Process is Used. — To obtain satisfactory results with these outfits, consideration should be given to the length of the sterilization period, which is indicated in the table below, in the column headed ‘'Process. ” Since the temperature cannot be controlled below the boiling-point, it is necessary to start counting the time when the water begins to boil and keep the boiling constant throughout the process. Complete steriliza- tion can be obtained by following this table if the essentials as outlined in other chapters are fulfilled.
Intermittent Processing.— The vegetable is processed for forty-five to sixty minutes at boiling temperature on each of three successive days.
QUESTIONS
1. Describe an outfit for processing by the hot-water bath which may be
made at home. Explain the principle which makes necessary each detail described above.
2. If purchasing a commercial hot-water outfit, what points should be
considered?
3. How will the position of the chimney on a commercial canner influence
the time needed to heat the water?
4. Describe a homemade fire-pot. What fuel may be used in it? In what
condition should the fuel be before placing the tools in it? Why is this care necessary?
5. Why do starchy vegetables require a longer processing than those
containing a large percentage of water?
6. Why is it necessary to keep the temperature constant during the
processing?
Canning Vegetables (Hot-Water Process)*
Do Not Attempt to Use this Table Without Reading All Directions Carefully
84
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86
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BIBLIOGRAPHY
1. Bitting, A. W. and K. G., “ Canning and How to Use Canned Foods,”
1916. Published by the National Canners’ Association, Washing- ton, D. C. 30 cents.
2. Bitting, A. W., Bulletin 9, “ Processing and Process Devices.” Na-
tional Canners’ Association, Washington, D, C.
3. Commercial catalogues from manufacturers of canners, glass and tin
containers, and other equipment.
4. Creswell, Mary E., and Poweel, Ola, U. S. Department of Agriculture,
Farmers’ Bulletin No. 853, “ Home Canning of Fruits and Vegetables,” States Relations Service, Office of Extension Work South. U. S. De- partment of Agriculture, Washington, D. C.
5. Creswell, Mary E., Georgia State College of Agriculture, “Home Can-
ning of Fruit and Vegetables,” 1915. Published by the State Col- lege of Agriculture, Athens, Ga.
G. “ Creole Cook Book,” 1914. Published by the Picayune, New Orleans, La. $1.25.
7. Farmer, Fannie Merritt, “ Boston Cooking School Cook Book,” 1907.
Little, Brown & Co., Boston, Mass. $1.80.
8^ McKimmon, Jane S., North Carolina Agricultural Extension Service, “ Canning and Preserving with 4-H Brand Recipes,” June, 1916. State Department of Agriculture, Raleigh, N. C.
9. Spring, Helen M., “ Individual Recipes in Use at Drexel Institute,” 1909. John C. Winston Company, Philadelphia, Pa. 25 cents.
10. United States Department of Agriculture, Bureau of Chemistry: In-
formation concerning state laws governing packages and labelling of canned products can be obtained from State Boards of Agriculture. Similar information concerning interstate shipment of canned products can be obtained from the U. S. Department of Agriculture, Washington, D. C.
11. United States Department of Agriculture, States Relations Service,
Office of Extension Work in the South: A-81, “Canning, Preserving, and Pickling”; 782, “Peppers”; 775, “Use of Vegetables from Winter Garden.” Can be secured from the Office of Extension Work in the South, States Relations Service, Department of Agriculture, Washington, D. C.
12. Vanderbilt, Sadie B., Columbia University, “ Phvsical and Chemi-
cal Tests for the Housewife,” 1913. Technical Education Bulletin No. 19. Teachers’ College, Columbia University, New York City, N. Y. 10 cents.
CHAPTER VII
PROCESSING AT HIGH TEMPERATURE
Steam Retorts. — Iron boxes or steel cylinders, known as retorts, are used in processing by steam at a temperature above the boiling-point (^. e., higher than 212° Fahrenheit) . The retorts may be vertical or horizontal, the size being determined by the number of cans to be handled daily.
In the vertical retorts steam may be used alone or it may be introduced into Avater; in the horizontal retorts steam alone is used. Vertical retorts are used where canning under high tem- perature is desired in the home, and in small canning plants. The steam pressure may vary from five to fifteen pounds, thus giving a temperature of 220° Fahrenheit (105° Centigrade) to 255° Fahrenheit (124° Centigrade). The proper control of time and temperature is very important. This is regulated by recording thermometers and temperature controllers attached to the retort.
Small Outfits for Home Canning. — An expensive equipment is not necessary when canning in small quantities at home. A variety of small steam canners for home canning are on the mar- ket (Fig. 61). The prices vary according to the size and quality of material used in making them. The construction of these out- fits resembles that of the regulation steam boiler. They are made of a high-grade metal, and the seams are so riveted, soldered, and joined as to make them water-tight and steam-proof. A band of packing is placed around the groove in the outer rim of the cover, which keeps the inside chamber steam-tight when the cover is clamped on. This part of the canner wears out after a time and should be replaced if the canner is to continue .to give the best results.
A brass pet cock which allows for the free circulation of steam and escape of dead air is screwed into the cover. This should be left slightly open while processing.
87
88
SUCCESSFUL CANNING AND PRESERVING
Fig. 62.
Figs. 61 and 62. — A steam retort for home canning. (Northwestern Steel and Iron Works, Eau Claire, Wisconsin.)
Fig 63 —Another type known aa the water-seal canner requires only a small amount ot water and it can be ridsed quickly to the boiling point with the use of very little fuel. A slight pressure can be secured.
PROCESSING AT HIGH TEMPERATURE 39
There is a dial gauge, the needle of which moves upward when the temperature of the interior of the canner rises above boiling (212° Fahrenheit). The figures on the face of the dial indicate the number of pounds of steam pressure and also its equivalent
Fig. 64. — Another steam-pressure outfit for home canning.
degree of heat. A safety valve is also aitached. The ‘ ‘ weight and arm” style valve automatically regulates the pressure inside the retort from one to fifteen pounds. The weight on the arm may be set at any point on the lever, as it is made to slide back and forth.
90 SUCCESSFUL CANNING AND PRESERVING
a certain time for the process is desired the steam gauge should be watched until it shows the required amount of pres- sure. Set the weight so that enough steam will escape from the valve to retain that temperature. After the processing the steam should be let off by raising the bar on the valve or by opening the pet cock before removing the cover of the canner (Fig. 64).
A wire basket or galvanized crate comes with the outfit. This is a great convenience, for it can be used in blanching, exhausting, and sterilizing. While sterilizing is in progress this basket or crate rests on a false bottom, which is sometimes made of galvan- ized iron. This permits of free circula- tion of steam underneath and around the cans. The capacity of a small retort is about 150 to 250 cans daily, and it will generate and hold about fifteen-pound pressure of steam. An outfit to be used in canning under steam pressure should be built of strong material and have suffi- cient attachments to determine and regu- late the temperature. The results of processing under steam cannot be as- sured without a thermometer; a gauge for reading steam-pressure is a substi- tute, since, as indicated in the table below, a definite pressure gives a definite degree of heat (Fig. 65) .
A steam retort may be converted into a hot- water canner by filling the canner with water and keeping it at a temperature of 212° Fahrenheit. Some outfits require that the steam be piped into the retort from a boiler tank. This is more often true with the larger and more expensive outfits (Fig. 66). Separate retorts which can be used over a stove or out of doors are made, and often gasoline burners are sold with them as a necessary accessory. Charcoal furnaces and a gas-flame oil stove will give good results, and they are less expensive and more easily handled. Other canners have a fire-box built in ; when used out of doors the fire is protected and steam can be obtained more quickly.
Fig. 65. — Pressure cooker.
PROCESSING AT HIGH TEMPERATURE
91
Fig. 66. — Commercial retorts where steam is piped in from the boiler. (Heinz Company)
Time-table for Processing by Steam
|
Name of product |
Blanch |
Season- ing |
Exhaust |
Temper- ature, F. |
Pressure in pounds |
Time No. 2 can, pints |
|
|
No. 2 |
No. 3 |
||||||
|
Degrees |
Minutes |
||||||
|
Asparagus |
Same |
Same |
Same |
Same |
\ 240 |
10 |
30 |
|
Beans |
240 |
10 |
45 |
||||
|
Beets |
228 |
5 |
30 |
||||
|
Brus.sels sprouts. . |
as |
as |
as |
as |
228 |
5 |
30 |
|
Corn |
250 |
15 |
80 |
||||
|
Egg-plant |
for |
for |
for |
for |
240 |
10 |
55 |
|
Hominy |
248 |
15 |
50 |
||||
|
Ckra |
hot- |
hot- |
hot- |
hot- |
248 |
10 |
30 |
|
Peas |
240 |
10 |
45 |
||||
|
Potato, sweet .... |
250 |
15 |
70 |
||||
|
Pumpkin |
water |
water |
water |
water |
240 |
10 |
65 |
|
Kraut |
1 |
228 |
5 |
20 |
|||
|
Spinach |
can- |
can- |
can- |
can- |
240 |
10 |
35 |
|
Squash |
234 |
8 |
65 |
||||
|
Succotash |
ning |
ning |
ning |
ning , |
248 |
15 |
40 |
|
Vegetable soup. . . |
228 |
5 |
35 |
Much time, labor, and fuel can be saved by sterilizing some of the heavy starchy products under steam pressure (see table above and Fig. 66).
92
SUCCESSFUL CANNING AND PRESERVING
QUESTIONS
1. What is meant by the term “ processing at a high temperature”?
2. For what kind of foods is this method particularly advantageous? Ex-
plain your answer.
3. What two points must be watched constantly while processing at a high
temperature? Explain your answer.
4. How would you examine a steam canner to determine its value?
5. What part of the best canner will deteriorate with use ?
G. What is the purpose of the pet cock”? Where is it located? How should this cock be while processing? Explain your answer.
7. Describe how to secure the pressure desired while using a steam canner.
8. When a definite time is desired for the processing, from what point in
this process will you count the time ?
9. What precaution should be taken before opening the canner? VHiy is
this necessary?
10. For what other method of canning may a steam canner be used? How can this be done?
BIBLIOGRAPHY See Chapter VIII, page 122.
CHAPTER VIII
FRUIT JUICES
Value. — The many ways of using fruit juices make them a most valuable product to have on hand throughout the year.
Medicinal. — Fruit juices were used almost exclusively for medical purposes until recently. It is still a common practice in Europe for physicians to send their patients to the vineyards to drink the fresh juices as they come from the press.
Daily Menu. — The juices of such fruits as grapes, currants, cherries, ‘blackberries, raspberries, plums, and apples make whole- some and delicious beverages, as well as being a pleasant addition to the daily menu. Nothing is more refreshing on a hot day than a cool fruit-juice drink, which may be easily prepared from bot- tled juices.
The dessert may be varied with very little expenditure of strength, time, and money by the use of different fruit juices. These may be used in making sherbets, ice-cream, puddings, sauces, and gelatine desserts.
Social Functions. — The combination of fruit juices makes an attractive fruit punch to be served at any social function.
GENERAL PREPARATION
i\Iuch depends on the methods used in picking, assorting, and cleaning the fruit used in making fruit juices, syrups, and vinegar.
Picking. — It is important to select only ripe fruit ; green fruit gives too much acidity to the finished product, while over-ripe or spoiled fruit imparts a disagreeable taste. Shallow trays or baskets are better adapted for picking, l)ecause they prevent crushing and bruising of the fruit.
Assorting. — Even after careful picking it is well to sort over the fruit on the trays, selecting only the sound fruit and discard- ing the green and rotted fruit.
93
SUCCESSFUL CANNING AND PRESERVING
94 ‘
Washing. — The fruit should be washed carefully to free it from adhering dust and dirt, which are always found in more or less amounts on freshly picked fruits. This is best accomplished by placing the fruit in a ware basket or colander and allowing a spray of water to run over the fruit. Often the fruit is bruised with the hands when wmshing it in a deep pail of water, so this method should not be used. It is important to use utensils w^hich will not be affected by fruit acids, and to preserve in glass storage containers, in all fruit-juice work.
EXTRACTING JUICES
The amount of work involved is relatively far less Tvhen the juice is extracted in large quantities than in small amounts, be- cause of the many labor-saving devices that are applicable if one is handling material in quantities.
Fig. 67. — Household fruit-juice press.
Cold Process. — This process consists of crushing and then pressing the fruit to facilitate the overflow^ of juice. An ordinary cider mill may be used for handling the fruit in quantities, but if only a small quantity is to be taken care of, the fruit may be crushed with a potato masher, food chopper, or fruit-juice press (Fig. 67). After crushing, the fruit is then pressed in a cloth by twisting the two ends in opposite directions (Fig. 68) until the greater part of the juice is extracted.
A homemade press may be constructed as follows :
FRUIT JUICES
95
Figure 69 shows a very efficient lever press which any farmer who is handy with tools can make for himself from material which can be found on almost any farm at any time. The press consists of the following parts : Two upright posts (F) are set deeply and firmly in the ground, about twelve inches apart. It is well to attach cross-pieces (ordinarily known as “anchors” or “dead men”) to the ends in the ground to prevent the posts from pulling out too easily. The lever {E) may be hung either between these posts by means of a bolt {T) or to the side of a building, or a hole large enough to admit the lever may be notched in a tree and
Fig. C8. — Cloth press being twisted.
a lever fastened by a bolt. At the other end are two posts, between which the lever can be raised by means of block and tackle. The press itself consists of two timbers {D) on which rests the press bottom {B). On this bottom is set a press basket (A), consisting of two sides and two ends held together by means of rods (L), and so constructed that it can be easily taken apart and put together again. The sides and ends are bored full of small holes, from three-eighths to one-half inch in diameter, through wdiich the juice is pressed. When the press is filled with fruit, the top, which fits inside the basket, and the cross blocks (7) are put on
96
SUCCESSFUL CANNING AND PRESERVING
and the lever caused to press down on them. A large tub {C) is placed under the press to catch the juice. The rope running through pulley block {G) fastened to cross-piece (K) is used to lift up the lever of the press ; while pressure or weights on the end of the lever {E) work the press.
For ordinary purposes a press basket three feet square and two feet high, holding a ton of crushed grapes, will be found to
Fig. 69. — Construction of a homemade fruit press.
Drawing made from illustration in U. S. Dept, of Agriculture Farming Bulletin No. 758.
be a very convenient size. It is perhaps well to state that the longer and heavier the lever, the greater the pressure exerted on the fruit. When it is not convenient to make the lever very long, weights are placed or hung on the outer extremity in order to increase the pressure. With a little ingenuity any farmer can adapt this press to suit his individual requirements. (Figs. 70 and 71.)
Sometimes in pressing grapes for beverages only the '‘free- run juice’’ is desired. This is the juice which is found between the skin and the pulp. Only sufficient pressure to burst the skin is necessary to secure this ‘ ‘ free-run juice. ’ ’ This gives a product which is more brilliant, clear, fragrant, and delicately flavored than the ‘ ‘ total juice. ’ ’
FRUIT JUICES
97
Hot Process. — Juices of small fruits may be prepared with or without previous heating, but heating before pressing increases the yield of juice, intensifies the color, and develops a more dis-
Fig. 70.
Fig. 71 .
Fig. 70. — Fruit press ready for use.
Fig. 71. — Fruit press in use. (Courtesy U. S. Department of Agriculture.)
tinctive flavor than can be obtained by simply cold pressing. There are, however, a few exceptions. Juices flow more readily from fruit when heated than when cold. When the fruit juice is to be used for jelly-making the hot pressing is necessary, because heat is essential to develop the pectin, the jelly-making sub- stance found in fruit juices.
7
98
SUCCESSFUL CANNING AND PRESERVING
If the berries or small fruits are to be heated before pressing, about one-half the quantity should be crushed with a wooden potato masher in the vessel in which it is to be cooked before heat- ing. Place the utensil containing the fruit over a second vessel containing hot water, so that the fruit may be steamed instead of stewed until tender. A better color and flavor will be retained if the fruit is not allowed to come in direct contact with the Are. The less juicy fruits require addition of water and a longer heat- ing to extract the juice.
Fig. 72. — A homemade fruit-juice filter.
Usual factory methods render the pomace, or cheese (the re- maining pulp), almost dry enough to burn. From an economical standpoint, squeezing the pulp is considered a good practice, ex- cept where the free-run juice alone is desired. When the juice is extracted it may be filtered by allowing it to drip through a flannel or felt cloth. Both the ‘‘free-run juice” and “total juice” should be carefully strained before bottling. After the juice has dripped through this filter, allow it to stand while the bottles are being sterilized, so that the suspended substances
FRUIT JUICES
99
present will drop to the bottom and render the juice less turbid. Now the clear juice may be poured off without disturbing the sediment. The juice which has been strained should be pro- tected from the dust. This can easily be done if a strainer such as shown in figure 72 is used.
PACKING
Reheating the Juice. — Some concentrated juices are packed cold, but thin juices will not keep unless heated to a temperature of 170° to 190° Fahrenheit. The temperature should never be allowed to go above 200° Fahrenheit. Fruit juices should never boil, because boiling injures the color and flavor. If a ther- mometer is not available to regulate the temperature, heat the juice in a double boiler and allow it to steam or simmer for five minutes.
Fig. 73. — Bottling fruit juice.
Bottling. — The preparation of fruit juices for bottling in the proper season requires little time and skill (Fig. 73). The juice should be poured immediately into hot sterilized bottles, allowing about one inch at the top for the expansion when the juice in the bottles is heated. If the juice is strained cold into the bottles, more space at the top should be allowed for expansion than when juice is packed hot. When juices are bottled for beverages, the addition of a small amount of sugar will produce a finer flavor.
100
SUCCESSFUL CANNING AND PRESERVING
The proportion varies, but a fair allowance is one cupful of sugar to one gallon of juice. No sugar should be added to the juice when it is bottled if it is to be used for jelly-making later. This method of allowing the bottled juice to stand undisturbed insures the getting rid of tartaric acid crystals in grape jelly which are so objectionable. On standing, the tartaric acid crys- tallizes and the crystals settle. When the juice is to be used for jelly-making it should be poured off carefully, so as not to dis- turb the sediment which contains these crystals.
Corking. — Soak new corks for one-half hour in warm soda water (one teaspoonful of soda to one quart of water), and then dip them into boiling water immediately before using. The corks should be placed loosely in the bottle before pasteurizing. Some- Times a small circle of cloth is tied over the cork during pas- teurization to keep it from blowing out. This is better than using a patented device. Neither of these will be necessary if sufficient space is allowed at the top of the bottle when filling with juice and the water-bath is kept at the proper temperature.
Pasteurizing.-— The term ^‘pasteurizing’^ is used here in place of sterilizing because of the low temperature used in heating fruit juices.
An ordinary wash-boiler makes a simple homemade pas- teurizer if fitted wil'h a false bottom. This false bottom prevents the bottles from coming in direct contact with the bottom of the vessel. A free circulation of water around all sides of the bottles will keep them from breaking. The vessel should be filled with water to within one inch of the top of the bottles. Heat the water slowly and allow it to simmer for twenty to thirty minutes, the length of time to depend upon the size of the containers used and the kind of juice being pasteurized. Testing the temperature of juice in the bottles with a thermometer gives greater accuracy. If this test is used, allow the corks to float on the water in the boiler until the pasteurization point is reached. Heat the juice to 140° to 150° Fahrenheit and hold this temperature for thirty or forty minutes, cork the bottles, and cool to temperature of 70° to 75° Fahrenheit before remov- ing the containers from the water-bath.
FRUIT JUICES
101
Sealing. — Immediately after the pasteurizing the sterilized corks should be driven tightly into the bottles to seal them securely. Place the neck of the bottle on the edge of the table and with a sharp knife cut the corks off even with the tops of the bottles and seal air-tight with melted paraffin or wax (Pig. 74). After cutting the cork, turn the bottle upside down and dip one inch of the neck into the melted wax, turning the bottle as it is lifted out to give a smooth coating to the sealing wax.
Fig. 74. — Making sealing wax.
Homemade Sealing Wax. — Melt together equal parts of shoemaker’s wax and resin. This should be done in a pan over hot water to prevent scorching and to make it a pretty amber color. Dip the corked bottles into it after it has melted. Various colors may be obtained by adding the following in given proportions to the melted wax. To each three pounds of resin used add:
For red color, 1/2 ounce Chinese vermilion.
For black color, 3 ounces lampblack.
For green color, 5 ounces chrome green.
For yellow color, 5 ounces chrome yellow, 1 ounce shellac.
For a white sealing wax, melt together 2 pounds white resin, 1 ounce white varnish, 1 {>ound beeswax, and % ounce zinc white.
102
SUCCESSFUL CANNING AND PRESERVING
Capping. — If a screw cap is to be placed on the bottle over the cork, the sealing wax should be omitted (Fig. 75). When a crown cap is used the bottles of fruit juice are usually pasteurized open and the cap crimped on by a hand machine immediately after the pasteurizing (Fig. 76).
Fig. 76. — A hand bottle sealing machine. (En- terprise Manufacturing Company, Philadel- phia.)
Labelling. — The appearance of the package depends a great deal on the label. Before labelling, wash and polish each “bottle. Place the label midway between the seams of the bottle and one- fourth inch from the lower edge. On each label should appear name of product, net weight stated in pounds and ounces, and the name and address of packer. Fresh clean labels should be placed on commercial bottles just before they are packed for delivery.
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Storing. — All bottled fruit juices should be stored in a cool, dark, dry place. If left in a bright light the color will fade and the juice will be less attractive. Unfermented juices properly made and bottled will keep indefinitely if not exposed to the air or to infection from mold germs. When a bottle is once opened the contents, like canned goods, should be used as soon as possible. The bottles or jars should be small enough so that the contents may be used at once, and not allowed to stand until they spoil.
SPECIAL PRODUCTS
Cider. — Cider making requires a comparatively inexpensive equipment and involves only a small amount of labor. Cider is not considered a profitable commercial product, because it is bulky and perishable. By following the methods given for bottling other fruit juices, fresh cider may be easily kept through the year. Usually cider is sterilized at too high a temperature, which destroys the delicate flavor of the fresh juice and renders it unappetizing. The length of time cider may be kept open before it ferments sufficiently to be considered as becoming “hard” or sour varies with temperature conditions and also de- pends oh the presence of fermenting agents.
Concentrated Cider or Apple Syrup. — The sugar percentage is low in fresh cider, and it contains so much water that the market for it is limited. Methods of reducing its bulk and chang- ing it into an article which will keep throughout the year have been devised. Attention has often been called to the fact that when ordinary cider freezes part of the water separates and freezes, leaving unfrozen a concentrated cider having natural cider flavor and a reduced water content, a higher percentage of sugar and other solids. Experiments in boiling down fresh cider to secure a concentrated syrup gave a product with a distinctly acid flavor, due to an excess of acid known technically as malic or apple acid. The problem resolved itself into removing the excess of acid, and this was finally accomplished by adding car- bonate or milk of lime to the cider, which precipitates the acid and, after settling or filtering and boiling, yields a staple and at- tractive table syrup. This syrup has a fine flavor and will keep
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indefinitely in sealed containers like syrup made from cane or sorghum. Small quantities for home use can he made with ordinary utensils.
Method for Making Apple Syrup. — The average farm house- wife who is provided with a large preserving kettle can easily make several quarts of apple syrup in her own kitchen. Although she may not find that she can sell her product profitably, she at least will find the method valuable in converting the windfalls of her own farm into a delicate and pleasant syrup for the use of her family. This product is a palatable and valuable food.
Method.^ — To make one gallon of apple syrup, stir into^ seven gallons of apple cider five ounces of powdered calcium carbonate (carbonate of lime), which is a low-priced chemical, readily obtainable from a local drug store in the form of pre- cipitated chalk or powdered marble-dust. Heat the cider and allow it to boil for a few minutes. As the cider will foam slightly, it is necessary to use a vessel at least one-third larger than the volume of cider. Pour the cider, after boiling, into vessels, preferably half-gallon preserving jars, which permit the condition of the liquid to be observed. Allow the liquid to settle until perfectly clear. This will take several hours or over night. After the liquid is perfectly clear and shows a distinct sediment at the bottom, pour off the clear portion into the preserving kettle, being careful not to pour off any of the sediment. Add to the clear liquid a level teaspoonful of the carbonate of lime and again stir thoroughly. The process is completed by boiling down the clear liquid. Inasmuch as the liquid when boiling down foams more than on the first heating, the kettle should be only one-third full when boiling commences. Where a large kettle is not obtainable, the liquid will have to be boiled down in batches. Allow the liquid to boil rapidly. If the housewife has a thermometer, she should allow the liquid to boil until it reaches 220° Fahrenheit. Where no thermometer is at hand, boil the liquid until it reaches about one-seventh of the original volume, or until a small portion when cooled rapidly
^From Year Book Separate 639, U. S. Department of Agriculture,
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and poured from a spoon shows about the same consistency as maple syrup. The aim is to make a thin syrup rather than one that will candy.
When the synip has reached this point, pour it off into the jars and let it stand where it will cool very slowly. Slow cooling is very important in making the syrup clear, as it allows all sediment and added substances to settle out completely. A con- venient way of bringing about this slow cooling is to put the vessels into a tireless cooker or to put the jars containing the syrup in a wa^-boiler, surround them with hot water, and allow the whole to cool. When the syrup has cooled to room temperature there will be found a white sediment, which is known to chemists as malate of lime, a harmless compound of the lime and the acid of the apples. This is identical with the product known as maple sand, which occurs naturally when maple sap is boiled down into syrup. When the settling has been com- pleted, carefully pour off the clear portion of the syrup into a kettle, heat nearly to boiling, and pour hot into sterilized jars, which should be at once sealed.
Another method would be to transfer the boiling syrup from the preserving kettle into the sterilized bottles and seal imme- diately. The sediment which appears at the bottom in no way affects the syrup. When ready to serve, simply pour off the clear portion, leaving the sediment, which is not easily disturbed, at the bottom. The syrup might also be bottled while cold, processed, and sealed as for fruit juices. The syrup will be a clear, ruby-colored product, possibly varying from a deep-ruby red to lighter shades, according to the character of apples used in making the cider. This syrup is similar in consistency to maple syrup, and can be used like any other table syrup. If made in accordance with these directions it will have a delicate and novel flavor, somewhat similar to that of the sugar which forms when apples are baked. It will be found that children will enjoy it on bread and butter, and that it will afford a new and useful flavoring adjunct or sauce for puddings or other desserts.
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Muscadine Grape Syrup. — The process of making Muscadine grape syrup is very simple, and with proper care an inexperi- enced operator can succeed. Since the making of grape syrup is very similar to the methods used in making apple syrup, it is unnecessary to outline the procedure in detail.
Varieties. — The varieties having the highest natural sugar and lowest natural acid content usually make the most delicious and highest quality syrup and also yield the most syrup per gallon of fresh juice. The Scuppemong, Thomas, Luola, Mish, and other similar varieties of high quality make the best syrups. The James makes a syrup of fair quality, while the Flowers and Eden varieties make syrups w^hich, relatively speaking, would be called acid and rough.
Pressing. — Cleanse the various parts of the press; scald it so that it wdll swell and will not leak. So soon as each pressing is completed it is important to remove all pomace from the press and to wash with clean water all the parts that have come in contact with the juice. This will prevent fermentation and souring at the press and the giving of foreign flavors to later lots of juice.
Crush the grapes and then press them cold. The free-run or first juice that comes from the press is more desirable for syrup making than that which is secured under pressure. This is principally due to the fact that the free-run juice is higher in sugar content and lower in acid content than the pressed juice. When pressure is applied the juice flows freely at first and then at a gradually slower and slower rate for many hours. The pomace should never be allowed to stand in the press longer than five or six hours. For many reasons it has been found desirable to press during the day, cook the juice the first time in the late afternoon or evening, allow it to stand in the precipitating jars over night, and boil it down to a syrup the next morning. A bushel of grapes will yield, w^hen cold pressed, from two and a quarter to four gallons of fresh juice, depending upon the variety. Most varieties yield at least three gallons. On this basis, condensing the juice to one-ninth of its volume, which has
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been found to give a syrup of satisfying consistency, one bushel of grapes, cold pressed, should yield one and one-third quarts of syrup. Heated grapes yield more juice than cold-pressed grapes, but make a syrup of inferior quality.
Heating. — Heat the juice and strain it. To every six quarts of fresh Muscadine juice stir in two ounces of powdered calcium carbonate (carbonate of lime) to remove the acids. Boil for six or eight minutes as with apple syrup, and pour hot into sterilized glass jars or pitchers. Allow the liquid to stand over night. Pour off the clear portion into a cooking vessel, being
Fig. 77. — Utensils used in making Muscadine syrup. (Courtesy U. S. Department of Agri- culture.)
careful not to pour off any of the sediment. Add one-sixth of a level teaspoonful of calcium carbonate for each six quarts of fresh grape juice which it represents.
Complete the process by boiling down the clear liquid, being careful to keep the caramel forming on the inside of the pan wiped off with a wet cloth so that scorched caramel will not fall into the syrup and cause it to have a burned flavor. Boil the liquid, being careful not to allow it to bum when it is nearly
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done. Skim during the cooking process and continue the cooking as for apple syrup.
Cooling. — When the syrup has reached the proper thickness, pour it off into the jars, cover, and place them in a hot- water bath or in a fireless cooker where they will cool very slowly. Slow cooling is important in order to obtain a clear syrup.
When the syrup has cooled to room temperature it can be bottled.
Bottling. — ^Pour off the clear syrup, leaving behind the sedi- ment, which is not easily disturbed. Bottle, sterilize, and seal at once (Fig. 77).
Fruit Syrups. — Fruit syrups which are left over from can- ning either small or large fruits should be bottled, pasteurized, sealed, and stored away to be used for flavoring or making beverages. A delicious drink is made by adding two or three teaspoonfuls of fruit syrup and the juice of one-half lemon to a glass of cold water. They may also be used for flavoring ice- creams, sherbets, and other desserts.
Such fruits as peaches, strawberries, and pineapples give more satisfactory results when made into syrups before bottling. Sugar helps to develop the flavor of these fruits. Sauces for sundaes and for flavoring are often made from red cherries, plums, currants, red and black raspberries, strawberries, black- berries, apricots, peaches, rhubarb, pineapples, and lemons. A good proportion to use for berries and small fruits is two cup- fuls sugar to each quart of juice.
For each quart grated fresh pineapple allow two pounds sugar to one cupful of water.
For each pound apricots, fresh fruit, allow one pound sugar to one pint of water.
For each two pounds peaches, fresh fruit, allow one pound sugar to one cupful of water.
For each quart rhubarb juice allow two pounds sugar.
For each cupful lemon juice, one tablespoonful of grated rind, allow one pound of sugar to one cupful of water.
General Method of Preparing Vinegar. — Cider vinegar is fre- quently made in the country home, but often when this product
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is put on the market it is found to fall short in one require- ment or another. The need of a careful study of this process is necessary, because the expense attached to its production is small, since Nature does most of the work, and can be utilized in the home or sold as one of the by-products to increase the income of the farm.
MAKING CIDER VINEGAR AT HOME ^
Why Study Was Needed. — The making of cider vinegar is a familiar operation in almost every farm home (Fig. 78). The final product is a necessity on every table, hhe small apples from which it is usually made are of practically no value for other purposes, the labor and expense of picking them up and pressing them are slight, and from the time the cider is in the barrel Nature does the work. Thus the process appears a simple one, easy to start, and self-operated to its termination in a salable commodity; so that the work-burdened farmer, with several barrels of cider in his cellar, may, in his few moments of leisure, think with pleasure of this farm operation which will bring him profit without further outlay of strength or money.
Yet vinegar is a food product and, as such, has come under the eye of state law, which says that to be legally salable the finished goods must meet certain requirements. Cider vinegar must contain 4.5 per cent of acetic acid and 2 per cent of cider vinegar solids before it can be lawfully sold, and frequently farmers who have made vinegar from pure apple juice only, and who have stored this under what they believe to be proper con- ditions for the proper length of time, find that their product falls short in one requirement or the other. Thus, without fraudulent intent or attempt at adulteration or dilution, the homemade vinegar falls under suspicion. Complaints of this condition reached the New York station in considerable number some years ago, and in an effort to find the cause or causes of the difficulty an extensive investigation of the subject has been made.
* These directions are quoted from X. Y. State Agricultural Experiment Station Bulletin No. 258, written by F. H. Hall.
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Cider has been pressed during different years and from different varieties of apples, and has been stored under varied conditions, with and without additions of yeast, “mother’’ or additional malic (apple) acid. In all, thirty-six experiments have been carried through periods of time varying from forty-four months to seven years. Each sample of cider was analyzed monthly for ten months and at two-month or three-month intervals after that time, attention being paid to seven constituents in most of the analyses; so that a great amount of data has been collected, of much chemical interest and practical value.
Simple Yet Complex. — As seen by the farmer, vinegar mak- ing is a simple process ; to the chemist, though less intricate than many other chemical transformations, it is complex ; while to the biologist the various steps in the change of sugar in the fresh apple juice to the acetic acid of vinegar are manifestations of very complex life activities of many species of organisms, divided into two great groups, yeasts and bacteria, each group perform- ing a specific function in the change. There may also come into action, under certain unfavorable conditions, other bacteria which hinder the useful transformations, or which destroy the prod- ucts desired and thus lower the quality of the vinegar. This interplay of living organisms, sometimes for good, sometimes for ill, has not been studied in all its details, and has been consid- ered, in this investigation, only as results were produced, the chemical transformations alone being considered.
Chemistry of Vinegar Making. — ^In a general way these transformations are two: Sugar, the ordinary cane-sugar and other forms known as invert sugars (dextrose and Igevulose), in the sweet cider, is first changed into alcohol through the fermen- tative action of one group cf organisms ; then the alcohol, by the action of a second group of organisms, is changed to acetic acid.
Chemically considered, each molecule of sugar consists of six atoms of carbon, twelve atoms of hydrogen, and six atoms of oxygen. When this molecule of sugar is acted upon by the proper ferments, it passes through a series of chemical changes which may be said to result, finally, in splitting it up into two molecules of alcohol, each containing two atoms of carbon, six of hydro-
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gen, and one of oxygen, and two molecules of carbon dioxide gas, each containing one atom of carbon and two of oxygen. This may be expressed in the form of an equation :
Sugar Alcohol Carbon dioxide
CeHijOj = 2C2H6O + 2CO2
Theoretically, we should be able to get from 100 parts of sugar by weight about 51 parts of alcohol and 49 parts of carbon dioxide; but because of evaporation and certain minor chemical changes we can get in practice only about 45 to 47 parts of alco- hol or less.
After the alcohol is formed, the organisms which act upon it begin the transformation to acetic acid. In this process oxy- gen is taken from the air. The result may be similarly repre- sented by an equation :
Alcohol Oxygen Acetic acid Water
C6H12O 4“ O2 = C2H4O2 “h H2O
Theoretically, again, we should obtain from 100 parts of alcohol about 130 parts of acetic acid, but we usually get less than 120 parts. So, starting with 100 parts of sugar in the apple juice, we may get under favorable conditions from 50 to 55 parts of acetic acid; therefore to have vinegar with 4.5 per cent of acetic acid we must have juice containing not less than 8.5 per cent of sugar.
Sugar in Apples. — This percentage, however, is found in practically all ripe, sound apples, although in a record of about 100 analyses of 80 varieties of American-grown apples, made at N. Y. station, in Washington, D. C., in Pennsylvania, and in Vir- ginia, five samples, of as many different varieties, were too low in sugar to produce vinegar of the required acidity. The sugar in apples reaches its maximum in ripe fruit, being low both in those that are green and those that are over-ripe. It averaged, in the apples used in the tests at N. Y. station, 13% per cent, and varied less than 2 per cent either above or below the average. A somewhat surprising fact to those not familiar with the chem- istry of the subject is that ‘ ^ sweet apples do not owe their sweetness to their large percentage of sugar, but to the small
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amount of malic acid they contain. For example, the sample of Red Astrachan juice contained 10.16 per cent of sugar and 1.15 per cent of malic acid; while Tolman Sweet and Sweet Bough contain about the same amount of sugar, but only 0.10 to 0.20 per cent of malic acid.
Alcoholic Fermentation. — Starting, then, with juice contain- ing sufficient sugar, what are the conditions which will best promote the changes to alcohol and to vinegar and prevent loss? The sugar must first be acted upon by the enzymes, or ferments, which are produced by yeast plants. The yeast germs are usu- ally present everywhere, so that they pass from the surface of the apples into the juice as it is pressed out, or fall into the cider from the air. It has sometimes been held unwise to wash apples before pressing them, for fear of carrying away the neces- sary yeast germs; but the apples used in all the station tests were washed without apparent interference with alcoholic fer- mentation. If apples have become dirty it is certainly best to wash them, as otherwise there is danger of introducing bacteria that interfere with proper fermentation. In ordinary cellar temperature, most of the sugar is changed into alcohol in five or six months, the change being slow during the first month, but quite rapid during the second, third, and fourth months. The process may be greatly hastened by storing in rooms warmer than cellars usually are during the fall and winter months. By placing bottles of vinegar in rooms of different temperature, running from 55° to 85° Farhenheit it was found that at 55° only 21/4 per cent of alcohol was formed in three months ; at 60° and 65° Fahrenheit, more than 41/2 per cent; and at 70° and 85° Fahrenheit, about 6% per cent was formed in the same time. At higher temperatures than this, evaporation of the alcohol would be liable to cause loss.
The addition of yeast also hastens alcohol formation, so that at a temperature of 55° Fahrenheit cider with yeast added gave 6^4 per cent of alcohol, and at 70° Fahrenheit, with yeast, 7i/4 per cent, both in one month. The use of any form of commercial yeast, if sufficiently fresh, will probably be found to give good results.
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Acetic Fermentation. — After the yeast fermentation has been completed the acetic-acid forming bacteria begin to attack the alcohol and produce acetic acid. This process is ordinarily very slow for about three months after the sugar has all been changed to alcohol (that is, during the eighth, ninth, and tenth months of cellar storage), but advances rapidly from the tenth to the fourteenth month and is practically completed in two years. This process also moves more rapidly, when once well started, at higher temperatures; but differences of temperature appear to have little effect during the three months after the sugar has disappeared. Beginning with the tenth month of storage, how- (iver, and up to the end of two and one-half years, nearly twice as great a percentage of acetic acid was produced where the temperature varied from 50° to 90° Fahrenheit as where it was from 45° to 65° Fahrenheit. The percentage of acid formed at lower temperatures never became as great as at higher tempera- tures, though part of the apparent increase in the warm room was due to evaporation of the water. The best results were secured at temperatures of 65° to 70° Fahrenheit.
It is the ordinary practice to add vinegar, especially vine- gar containing mother,” to the barrels in which vinegar is making; and the investigation proved the practice a most excel- lent one, as the acetic fermentation was more rapid and more complete in every case where this form of inoculation or ‘‘seed- ing” was used. This addition of “mother” is comparable to the addition of a “starter” in souring milk, for the “mother” is produced by the growth of the acetic bacteria in the presence of air and contains large numbers of .these bacteria.
It appears to be of advantage in some cases to draw off the clear portion of the cider after alcoholic fermentation has been completed, leaving the dregs; and to continue the process in new, clean barrels or to wash out the settlings and return the clear liquid to the barrels. This proved of considerable advan- tage in the case of vinegars stored at low temperatures, but of less utility when the vinegar was stored at higher temperatures where the acetic fermentation proceeded rapidly. Possibly with cider made from uneleaned apples and carelessly strained juice 8
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the results along this line would be more striking; for the liability to contamination with undesirable germs would be greater in such cases.
Loss of Acetic Acid. — In both alcoholic fermentation and acetic fermentation the air should have free access, especially in the latter; for, as can be seen by the equation given to explain the process, oxygen must be added to alcohol to make the acetic acid, and this must come largely from the air. On this account the barrels should not be filled more than two-thirds or three- fourths full with the apple juice or with the ‘‘hard” cider. But when the acetic fermentation has ceased to be active and the amount of acetic acid is safely above 41/2 per cent the vinegar should be drawn from the barrels and strained, the barrels cleansed, the vinegar returned, filling the barrels full, and the bung driven in tight.
Unless this is done, destructive fermentation may begin and the acetic acid decrease instead of increasing. In several experi- ments where the vinegar was held in loosely stoppered casks or bottles it lost all or nearly all its acid, and in some cases actually became alkaline in reaction. This destructive fermentation may be due to new species of bacteria introduced, or even in some cases to the same acetic acid-forming species which, when the alcohol is exhausted, attack the acetic acid itself.
As showing how complex may be the processes passing in 'dnegar, the case may be cited of four one-quart bottles of the same juice stored under the same general conditions. At the end of five years bottles A and B contained 5.74 and 5.44 per cent, respectively, of acetic acid, bottle C 2.10 per cent, and bottle D gave an alkaline reaction. Bottles A and C contained nearly three times and bottle B two and one-half times as much solids as bottle D.
Malic Acid. — The acid of fresh apple juice is not the acid of vinegar, but a fixed acid called malic acid. This has certain chemical characteristics which make it quite easily recognizable ; and so its presence in vinegar has been considered an index to determine whether the vinegar was or was not truly vinegar from apples. But these investigations have proved that this acid dis-
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appears quite rapidly from vinegar, . so that in twenty-four months it had shrunk from an average of 0.55 per cent to 0.02 per cent; while in some older vinegars it had disappeared en- tirely. The relation of malic acid to cider vinegar is being further studied.
Legal Standard. — The legal standard of the state for acid, 4% per cent of acetic acid, has been upheld fully by these results; for apple juice from good ripe apples, properly managed in fermentation, should and does easily give 4i/^ per cent of acetic acid within two years at cellar temperatures and in less time at higher temperatures.
Concerning solids, the wisdom of the standard is not quite so clear. In several experiments made in this investigation, vine- gars made from pure apple juice and well above the limit in acid contain less than two per cent of solids.
Conditions Producing Poor Vinegar. — Among the conditions which may produce vinegar below’ standard are these: (1) The juice may be poor to start wdth because made from varieties of apples low in sugar, from green apples or from over-ripe or de- cayed apples; or the juice may be watered either directly or by w’atering the pomace and pressing a second time. (2) The fer- mentation processes may be delayed or disturbed by using dirty fruit or unclean barrels, thus affording entrance to undesirably organisms and causing the w’rong kind of fermentation ; the tem- perature may be too low to insure the necessary activity of favor- able organisms; or air may be excluded by filling the barrels too full or putting the bung in too tight so that the bacteria can- not live and work. (3) The acetic acid may disappear after its formation, destructive fermentation being encouraged by leaving the bung-hole of the barrel open or the barrel only partially full.
To Make Good Vinegar. — Briefly summarized, the method to be employed for the manufacture of good vinegar at home, with- out the use of generators, is this : Use sound, ripe apples, picked or picked up before they have become dirty, if possible, other- wise washed. Observe the ordinary precautions to secure clean- liness in grinding and pressing, and discard all juice from second pressings. If possible, let the juice stand in some large recep-
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tacle for a few days to settle, then draw off the clear portion into well-cleaned barrels which have been treated with steam or boil- ing water, filling them only two-thirds or three-fourths full. Leave the bung out, but put in a loose plug of cotton to decrease evaporation and to prevent the entrance of dirt. If these barrels are stored in ordinary cellars, where the temperature does not go below 50° or 45° Fahrenheit, the alcoholic fermentation Avill be complete in about six months; but by having the storage room at a temperature of 65° or 70° the time can be considerably shortened, and the addition of compressed yeast or its equivalent at the rate of one cake to five gallons of juice may reduce the time to three months or less. Use a little water to thoroughly disintegrate the yeast cake before adding it to the juice. The tem- perature should not go above 70° for any length of time, to avoid loss of the alcohol by evaporation.
After the sugar has all disappeared from the juice (that is, when the cider has entirely ceased “working” as revealed by the absence of gas bubbles), draw off the clear portion of the cider, rinse out the barrel, replace the liquid and add two to four quarts of good vinegar containing some “mother,” and place at a temperature of 65° to 75° Fahrenheit. The acetic fermenta-
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tion may be complete in three months or may take eighteen months, according to the conditions under which it is carried on ; or if stored in cool cellars may take two years or more. If the alcoholic fermentation be carried on in the cool cellar and the barrel be then taken to a warmer place, as outdoors during the summer, the time of vinegar formation may be reduced from that given above to fifteen or eighteen months. Where the alco- holic fermentation is hastened by warm temperature storage and the use of yeast and the acetic fermentation favored by warmth and a good vinegar ‘‘start,” it is possible to produce good merchantable vinegar in casks in six or twelve months.
When the acetic fermentation has gone far enough to produce 4.5 to 5 per cent of acetic acid, the barrels should be made as full as possible and tightly corked in order to prevent destructive changes and consequent deterioration of the vinegar.
RECIPES
Bottling Juice of Grape Fruit. ^ — Bring the grape-fruit juice to the boiling-point in a porcelain-lined or enamelled kettle, pour it while still hot into sterilized bottles, and seal hermetically. The juice when so handled will keep indefinitely, and provides a base for “ grapefruitade ” or other acid beverages having the characteristic acid, somewhat bitter, flavor of the fruit. Experi- ments show, however, that it is highly important that the bottle be completely filled, so that no layer of air will be left between the top of the juice and the cork or seal. When air in any amount comes in contact with the top of the sterilized juice it will cause the juice to change its color. In handling the juice it is particu- larly important that it be kept from coming into contact with iron or other metals easily acted upon by fruit acids.
The investigators found also that it was possible to freeze the grape-fruit juice into solid ice and then, by whirling the ice in a centrifugal machine, to take out a larger part of the water and leave the solids and flavoring matter of the fruit. This freezing and concentrating of the juice greatly reduces the bulk and
®This recipe was prepared by the Bureau of Chemistry, U. S. Depart- ment of Agriculture.
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makes a product which can be sterilized by heating and kept indefinitely.
Clarifying Juice. — Those who wish to make a clear juice may filter the grape-fruit juice before it is heated by adding to it from two to three per cent (about three ounces avoirdupois to the gallon) of infusorial earth well washed with hot water. The mixture is then forced through a non-metal lie filter-press and the clear juice reheated and boiled. With the freezing process, the juice is filtered after concentration, about twice the amount of infusorial earth being used per gallon of concentrate.
The chemists, in connection with this bottling of grape-fruit juice, notify the public that the same process is not suitable for bottling the juice of oranges and lemons, which will not retain their fiavor if handled in this way.
While as yet, so far as knowm, there is no commercial market for sterilized grape-fruit juice, it is believed that many persons will find this juice, with the addition of water and sugar, a pleasant variation from lemonade or limeade. Those who like grape-fruit should find the beverage inviting. The method is so simple that those in regions where grape-fruit are cheap and plentiful can prepare this product on a small scale with ordi- nary household appliances.
Bottling Grape Juice. — Juice compressed from the various cultivated grapes can be bottled. Recipes follow for leading Southern and Northern varieties.
Scuppernong Grape Juice. — After washing the grapes, crush while heating them. Fruit juice will fiow more readily when the fruit is heated, but the pulp should not be allowed to boil. When the pulp is thoroughly soft, strain through a double cheese- cloth and squeeze as much juice through it as possible, then strain the juice through a flannel cloth without squeezing. This will give a clear juice. After this heat the juice to 180° Fahrenheit, skim and strain into sterilized bottles, place the corks in loosely, place the bottles on a rack in the water-bath, and pasteurize for fifteen minutes at a temperature of 180° Fahrenheit. Pound the cork in tightly, dip the top of the bottle into sealing wax, and store away in a dark, dry place. If this juice is to be used for a
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beverage and sugar is desired, it may be sweetened to taste be- fore heating and pouring into the bottles.
Scuppernong juice packed in this way can be used for making jelly later in the season. However, the jelly made from this juice will not be firm enough unless half the quantity of the grapes used are green and the other half ripe. The green grapes will furnish sufficient pectin to give it the proper consistency, and the ripe ones will furnish the color and flavor.
Unfermented Concord or Niagara Grape Juice. — To every five pounds of Concord or Niagara grapes use one pint of water. Crush grapes, add water, bring to boil, and strain through jelly- bag. Add one-half cupful of granulated sugar to every quart of juice. Bring just to a boil and pour into sterilized bottles, pasteurize, and seal air-tight.
Berry shrub may be made of strawberries, raspberries, or dewberries. Select sound fruit, wash, measure, and place in a stone jar. For every four quarts of berries use one quart of vine- gar. Cover the jar by tying a cheesecloth over it. Stir the berries daily for three or four days. If the weather is very warm do not let it stand over three days. Strain without squeezing and put into kettle, allowing one pound of sugar to each pint of liquid. Boil slowly for five minutes, bottle, cork, and seal. Dilute with cold water for serving.
WAYS TO USE FRUIT JUICES
Grape Cup. — To three pints of grape juice add four whole cloves, one cupful of sugar, the juice of four oranges with one- half grated orange rind and a few leaves of lemon verbena or mint. Bring to boiling-point, cool, and let stand to ripen for two or three hours. When ready to use, stir in the stiffly beaten whites of three eggs, a quart of unfermented grape juice, and a pint of water, and serve in tumblers with ice.
Fruit Cup. — Two tablespoonfuls of green tea, two quarts of boiling water, two cupfuls of sugar, juice of one orange, one cup- ful of currant juice, juice of two lemons. Pour water over tea, let stand five minutes, then strain over the sugar ; add lemon and orange juices, cool, and let ripen in a cool place for six hours.
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SUCCESSFUL CANNING AND PRESERVING
When ready to serve, add the currant juice, pour over cracked ice in deep glasses, garnishing each serving with a small, old- fashioned yellow rose or a sprig of mint. If desired, the cracked ice may be omitted, the punch being poured over raspberry ice or peach or pineapple sherbet instead.