l8o BACTERIA, YEASTS, AND MOLDS 



easily preserved than others. Meats are preserved with 

 great ease, but it is rarely worth while in the household 

 to can meat, since fresh meat can be bought in civilized 

 countries at all seasons of the year. When one wants 

 canned meats it is better to depend upon the product 

 bought in the market than to go to the trouble of canning. 

 The same may be said of tomatoes, corn, peas, or beans. All 

 of these materials may be canned successfully in an ordi- 

 nary household, but it requires long heating and special 

 care, and at best there will be many failures. Consequently 

 such materials, when canned in the home, may be very 

 expensive because of the considerable amount that must 

 be thrown away. In the canning factory, however, because 

 of greater experience and better facilities, these foods 

 can be preserved much more successfully and cheaply. 

 Moreover the commercial products in these cases are of a 

 very satisfactory quality and very cheap. If for any reason 

 a housewife has on hand a large quantity of tomatoes 

 which must be canned or thrown away, it may be econom- 

 ical to can them at home, always remembering that they 

 require more heat and more care than most other fruits. 

 But except under such conditions it is better and cheaper 

 to depend upon the market for canned tomatoes, peas, and 

 corn. The market products are more reliable, consider- 

 ably cheaper, and usually nearly or quite as good as those 

 obtained by home canning. 



Concerning other materials, however, it is economical 

 and frequently advantageous to adopt the process of can- 

 ning in the household. Most forms of fruit — apples, 

 pears, cherries, peaches, grapes, berries, etc. — are canned 

 without much difficulty, requiring only a moderate boiling 



