The Preservation of Food in the Home. — Part I 1265 



organism, which, having escaped in some way the destructive action of 

 heat, feeds on the food and causes it to mold, ferment, or decay. We may 

 ponder on this problem and wonder how, with all our care, our failure could 

 have occurred. We may say, " Why, last year I canned a hundred quarts 

 of tomatoes and lost only one or two cans and I do not believe I was so 

 careful in preparing them as I was this year; and just look at the results, 

 nearly half the tomatoes are spoiled already." But the failure has come, 

 nevertheless, and it is not our part to bemoan this year's " spoils " but 

 to prepare for next year's success by finding the cause of failure. One 

 thing we know, and we know it absolutely, and that is that it is the presence 

 of some living thing which has caused the food to spoil — that in some 

 way we have failed to destroy, in the food or in the can or on something 

 that has come in contact with either, every persistent, annoying micro- 

 organism. 



The housekeeper is not the only person who has suffered, from a tem- 

 porarily unexplainable reason, because of spoiled food. She owes a great 

 debt to the commercial canner, who has suffered similarly, for the solution 

 of some of her problems. The commercial canning problem was large 

 enough financially to urge immediate solution, when a few years ago a 

 man found his carefully canned peas, distributed in different towns, 

 returned with complaint. They certainly had spoiled in the cans, thus 

 involving financial loss, some damage to a good firm's reputation, and much 

 annoyance. But what was the cause of this state of things ? The scientist 

 began to investigate and it was found that the peas grown that year were 

 infected with a type of micro-organism that was able to resist the heating 

 which in previous years had been sufficient to insure the keeping qualities 

 of the peas. The investigations led to much experimenting in behalf of 

 the home as well as of the commercial industry, so that at the present 

 time the home canning of foods has been brought to a point where neaily 

 all foods may be successfully canned. 



Factors involved in canning fruit. — The present status of the best methods 

 of canning foods in the home may be explained briefly. It is now known 

 that some micro-organisms which cause foods to spoil may assume two 

 forms, the spore and the vegetative forms. When conditions are unfavor- 

 able to their growth they go into the spore form, cease growing and repro- 

 ducing, and become inactive and very resistant to outside influences. It 

 is their m^ethod of tiding over a hard time. In the spore form micro- 

 organisms are much more difficult to destroy and some of them are able 

 to resist a temperature even a,s high as the boiling point of water, for an 

 hour or more. During a dry season the spores occur much more frequently 

 than usual on fruits and vegetables, and the difficulties of successful can- 

 ning may, therefore, be greater. As soon as growth conditions become 

 favorable — that is, when warmth, moisture, and food are supplied — 



