This section is from the book "Save It For Winter.", by Frederick Fry Rockwell. Also available from Amazon: Save It For Winter; Modern Methods Of Canning, Dehydrating, Preserving And Storing Vegetables And Fruit For Winter Use, With Comments On The Best ... For Saving, And When And How To Grow Them.
As soon as vegetable food products mature or are gathered for market or for the home table they begin to deteriorate, and in most cases within a very short time become decayed, shriveled, or otherwise unfit for use as food.
Why does food spoil?
The answer is to be found in that now well-known household word-"bacteria."
Bacteria, or vegetable molds, in such forms that they are not visible to the naked eye, are ever lying in wait to attack the surface or the tissues of every form of vegetable life immediately the latter dies or is killed by harvesting. Some vegetables, however, naturally go through a dormant period after actual growth ceases, before their natural cycle of life is completed. These things, which are generally termed "non-perishable" vegetables or fruits, are, under favorable conditions, more or less immune for a certain length of time from the attacks of the destructive bacteria. Even these food products, however, will quickly "spoil," either as the result of being attacked by bacteria or through partial evaporation of the moisture which they normally contain, if the conditions under which they are kept are not similar to those provided by Mother Nature in the plan of existence which she has worked out for them.
How, then, are our foods to be kept from spoiling?
Our first problem, of course, is to find some means of keeping the destructive bacteria away from the product which they are waiting to attack and destroy. This can be done either by keeping them away by a physical barrier from the product, or by furnishing conditions which are unfavorable to the existence of the bacteria themselves. In the case of non-perishable products such as po tatoes, many root crops, and some fruits, we must supply conditions similar to those which nature intended and which will discourage the development of the obnoxious bacteria.
By what means may these results be accomplished?
There are, to use common terms, four methods of accomplishing these results:
First, by canning.
Second, by drying.
Third, by pickling or preserving.
Fourth, by storing.
All of these words are familiar household terms to the layman; yet, without a doubt, not one out of ten persons who use these terms ever stops to think how the various methods accomplish what they do accomplish, making it possible for us to eat three square meals for three hundred and sixty-five days in every year. Any one who is interested in saving food should have a working knowledge of the general principles upon which the ordinary methods of saving food are based. Such knowledge should be had not merely as a matter of information but because it is of practical use in enabling one to do the work intel ligently and accurately, thus assuring better results.