PLAN No. 560. KNEW THE SECRET OF HOME CANNING
Most of the housewives in America believe that home-canned vegetables nearly always spoil. That is because they do not understand the important part played by bacteria in the canning process. Vegetables contain a large amount of proteid, the favorite food of bacteria, and unless these bacteria are destroyed, vegetables canned in summer are almost certain to spoil.
On the other hand, fruits—and these include tomatoes—contain but little proteid, but a great amount of acid, (which bacteria especially dislike) and are therefore much easier to can, as well as to keep.
A young farmer’s wife in Illinois, who had made a close study of bacteria, knew exactly what to do in the matter of canning vegetables. She knew that bacteria, in order to protect themselves even against the heat of boiling water, form thick-walled bodies or spores, and that the first boiling simply causes the spores to grow, while a second or a third boiling effectually destroys them. She has tried this method often enough to be sure of it.
She therefore wrote a little booklet on “How to Can Summer Vegetables,” placed the price at 50 cents per copy, and advertised it in a number of women’s magazines and other periodicals. Many answers came in, enclosing 50 cents, and she sent out thousands of copies during the first three months. Often people make special study on certain subjects and have special experience along that line which if put in pamphlet form would be valuable to other people who would be willing to pay 25 to 50 cents for it.