The great secret of canning lies in complete sterilization. All fruits and vegetables, as well as the water we drink and the air we breathe, are teeming with minute forms of life called bacteria or molds or germs. These germs are the sole cause of decomposition or rotting, and are the only causes of spoilage we have to deal with in canning.
The exclusion of air from canned articles is not necessary provided the air is sterile and free from germs.
Fruits are usually slightly acid, and in general do not support bacterial growth, but are more commonly fermented by yeasts. In order to retain the natural flavor of the fruit little sugar should be used, and the fruit should be cooked only long enough to insure its preservation. It is unnecessary to boil the syrup previously. The sugar may be dissolved in cold water in right proportion to the kind of fruit used, and poured over the fruit in the jars. The fruit should be perfectly sound and not overripe. It should always be sorted; ripe fruit and hard fruit should never be cooked in the same jar. All stewpans, strainers, glass jars, and tops should be put on in cold water, heated to the boiling point, and then boil for ten minutes before using. The quantity of sugar used will vary with the kind of fruit used, and somewhat with the locality in which it is grown. The following proportion is taken as an average, more or less sugar may be used as the ca-e may require:—
2 quarts water to 1 quart sugar Peaches, 3 " " " 1 " Pears, 3 to 4 " ** " 1 " Plums, sour 1J " " " 1 "
Berries may be canned by this method, using about two pounds of sugar to ten pounds of berries, add the sugar to the stemmed and washed berries, let stand one hour, fill jars and cook the same as for ripe apricots. Most people prefer to bring the berries to boil on top of the stove with sugar needed, and fill them into hot glass jars and seal them.
Preferably canned whole. Wash and pack into glass jars, put on the rubber ring, and fill with syrup. Screw the covers on loosely, and set the jars into a boiler with a false bottom in it to keep the jars from resting on the bottom of the kettle. Pour cold water into the boiler until the jars are about two thirds immersed in water. Heat gradually to the boiling point, and let boil for ten minutes after boiling begins. Then remove the cover from one jar and stick the point of a knife into the fruit, if it is quite tender, set the jar into a shallow pan of hot water and run the blade of a silver knife down the side of the fruit to let the foam rise to the top; fill to overflowing with boiling syrup and screw the top on tightly. Turn up side down on the table to make sure there is no leak. Let it remain thus until next day, then wipe the jar with a damp cloth and set the fruit in a cool, dark place.
Use free-stone peaches. Peel and cut them in halves, removing the stones, except that a few may be put into each jar for flavor. Pack the fruit into jars, and finish the same as for apricots.
Peel and cut the fruit into halves. Remove the seeds, etc., and proceed in the same way as for peaches.
Wash and peel the plums, saving out the small ones and the peel for jelly. Pack the fruit into jars and finish the same as apricots.
To each fifteen pounds plums and peel, add about two quarts cold water, and set on the stove, care being taken not to burn them. When they are thoroughly done, pour into a bag or cloth in which the mesh is not woven too closely together, and hang up to drip. To each quart of juice thus made add one quart of sugar and bring to boil; skim, and let it continue to boil for thirty minutes, if only one quart of juice; forty minutes, if one gallon; and about fifty minutes to one hour for five to ten gallons. Take glasses out of hot water and fill, let them stand forty-eight hours, then pour over them enough hot parafine to cover.
If plums are picked just after a rain or heavy dew, they will contain much more water than otherwise, then they will require less water, and it is always safest to boil a small quanity first as a test before making a large quatity of jelly.
The spoiling of vegetables is due primarily to bacteria. Being much more resistant to heat than yeasts, they require longer cooking than fruits. While the parent bacteria may be destroyed by a temperature of boiling water, the seeds or spores retain their vitality at that temperature for a long time, and upon cooling will germinate and begin their destructive work. Therefore it is found necessary, in order to completely sterilize a vegetable, to heat it to the boiling point and keep it to that temperature for one hour, for two or three successive days.
Break the ends off, remove strings, wash, drain, and pack them into cans provided for that purpose. Make a solution of one ounce salt to two and one-half quarts water, and pour it on the beans, filling the cans four-fifths full. Solder tightly, and when they have boiled one hour, puncture the end to let out the steam, then in five minutes resolder and let remain until next day, when they should be boiled one hour more, and on the third day repeat the boiling. They may then be stored. They need not be punctured except after the first cooking.
Secure young corn. Scour down the rows and press out the pulpy material; add enough salted water to make it quite soft, using a preparation of one ounce salt to one and one-half quarts water, and finish the same as string beans. A very little sugar should be added to the corn, also to green peas, which are canned by the same method.