No. G. DEPARTMENT OF AGRICULTURE. 275 



is selected with reference to tomatoes, the addition of a few small 

 pieces would complete the outfit for canning- fruits and pumpkins. 



A similar outfit for canning corn with a capacity of 40,000 cans 

 per day, including the best modem machinery is estimated to cost 



$8,500. 



THE VARIETY OF FOODS PUT UP IN CANS. 



The variety of foods that is put up in cans and jars is exceedingly 

 great and has not yet reached its limit. It is estimated that about 

 400 varieties of fruits, vegetables and meats are successfully packed 

 in their season, and over 4,000 "brands" of these have been registered 

 in the United States. The inferior qualities which in former years 

 held canned goods under suspicion are now seldom met with; a bet- 

 ter grade of raw materials is used and more care and cleanliness in 

 canning is exercised. Reports of XJoisoning from the use of foods 

 from tin cans are much less frequent. However, the cases of al- 

 leged poisoning by canned goods have never been reported over the 

 signature of a reputable physician. It is a well known fact in most 

 households that when a can is opened its contents must be removed 

 from the tin at once or under the influence of the air an action will 

 take place and render the food unfit for use. The neglect of this 

 precaution, especially with tomatoes and similar acid foods, has 

 caused cases of sickness. 



PROCESSING. 



The most particular work in canning foods successfully is what is 

 known in the factory as the ''process," and for which a responsible 

 man known as the i^rocessor is- an absolute necessity. He was once 

 supposed to have locked up in him great secrets without which 

 canning could not be properly done. His importance, however, is 

 not diminished in the slightest degree by the disclosure of the prin- 

 ciples of his processes, for his peculiar and ''mysterious" power rests 

 in his experience and good judgment m performing his particular 

 work. Processing simply means the cooking of the canned goods 

 at such a degree of temperature and for such a length of time that 

 the contents of the can will be effectually sterilized and cooked ten- 

 der. The length of time required varies with the article being canned 

 and the temperature under which the boiling takes place. Two 

 kinds of processing kettles are used; the opeti top and the closed top 

 kettles. In the former, boiling takes place at 212° F. and no higher 

 temperature can be secured. This is known as the open hath pro- 



