HOME PRESERVING AND CANNING 



161 



Fig. 236. Harvesting tomatoes in Cali- 

 fornia, The vines cover the ground. 



cauliflower, are distributed largely in logging, 

 mining and construction camps, and in cold and 

 remote regions where fresh supplies cannot be 

 secured. 



It is generally thought that the industry will 

 not show the rapid growth in the future that it 

 has in the past, for the reason that communities 

 formerly dependent on canned goods for their 

 supplies of fruits and vegetables, are now in many 



cases growing, 

 and even can- 

 ning, their own 

 products. In 

 other cases, 

 with the im- 

 proved s h i p - 

 ping facilities 

 and extension 

 of railway 

 lines, compara- 

 tively remote 

 communities are now able to receive apples, citrous 

 fruits and vegetables in safety throughout the 

 winter. The constant improvement in the quality 

 of dried fruits and their relative cheapness has 

 had the tendency to reduce the volume of business 

 on the cheaper grades of canned fruits. On the 

 other hand, the demand for the better grades shows 

 gratifying increase, and the development of new 

 markets offsets the falling off of others. 



HOME PRESERVING AND CANNING 



By Anna Barrows 



Primitive man early discovered that dried foods 

 are more easily transported from place to place 

 and have better keeping qualities than when fresh; 

 and that the salt of sea-water and the smoke of 

 the camp-fire have further preservative influence. 

 Generations ago housekeepers found out that dense 

 substances would keep longer than those that were 

 •watery, so they packed cooked meat in its own fat, 

 and made preserves rich with honey, or sugar, and 

 savory with spices. The air-tight tin can and glass 

 jar, sterilization and cold-storage, have done much 

 in solving one of the most complicated problems of 

 modern civilization, but all the possibilities have 

 not yet been fully investigated. 



The efficiency of all ancient processes of food 

 preservation is explained by the later knowledge 

 of the habits of microorganisms. Failure in can- 

 ning and preserving is usually due to lack of knowl- 

 edge of these subjects. The essential points are 

 these : Bacteria do not thrive in substances con- 

 taining less than 25 per cent of water, such as 

 preserves or jellies thick with sugar ; they are 

 destroyed by heat; they do not flourish in the 

 presence of acids, alcohol, salt, spices, or the sub- 

 stances deposited by smoke. Foods containing 

 little nitrogenous matter are less liable to the 

 attack of bacteria; therefore bacteria are less 

 troublesome in the preservation of fruits than of 

 fish and meats. 



Molds and ferments or yeasts are the common 



Bll 



Fig. 237. Forms of yeasts of 

 different kinds. 



enemies of preserves, jellies and the like. (Figs. 

 237, 238.) These growths usually are killed in a 

 few minutes at the temperature of boiling water, 

 212° Fahr. A lower degree of heat continued for 

 a longer period — half 

 an hour or more — is 

 often as effectual and 

 less detrimental to the 

 fiavor and texture of 

 the fruit. The spores, 

 or undeveloped organ- 

 isms, resist heat that 

 would be fatal to those 

 fully grown, so in lab- 

 oratories or canning 

 factories steam, under 

 pressure, is used to 

 secure a temperature 

 much higher than 212° Fahr., and thus wholly to 

 sterilize the food. Here the housekeeper cannot 

 compete with the factories, and must practice 

 intermittent sterilization as was done long before 

 the existence and habits of these microorganisms 

 were known. The material to be sterilized is 

 heated to the boiling point and kept there for half 

 an hour on three or more successive days. Between 

 these scaldings it is left at an ordinary tempera- 

 ture, that the spores may germinate and become 

 active organisms. These are then killed by the next 

 heating, and after the final boiling the exclusion 

 of air prevents the entrance of others. 



It is essential that everything exposed to the 

 air, filled as it is with " germs," should be sterilized 

 before it comes in direct or indirect contact with 

 the food to be preserved. Fruits are constantly 

 exposed while growing, or in market, and their 

 skins harbor vast numbers of microorganisms; hence 

 they must be thoroughly washed. The removal of 

 skins from peaches, tomatoes and like products by 

 scalding has more than one beneficial effect. If 

 pared fruit must stand before cooking, it should be 

 dropped into water with lemon juice or vinegar in 



Fig. 238. Molds. .A.Mueor, showing sporangia bearing spores; 

 B, Peneillium, showing conidiophore bearing spores, 



it, to prevent the discoloration probably due to the 

 action of a ferment. 



The room in which such work is to be done 

 should be as clean as the operating-room of a 

 hospital. All possible dust should be removed with 

 a damp cloth. Every utensil should be boiled ten 

 minutes or more, and kept in the water till it is to 

 be used. The jars had better be filled over the 

 stove where the air is sterilized by heat and steam, 

 rather than by an open window, where dust-laden 

 air can come in contact with them. 



We have become so accustomed to certain flavors 



