Fruit canning is a very simple process, but if it is perfectly successful, certain principles must be followed : - 1. All germs' must be killed and excluded.
2. Only good, sound fruit should be used.
3. Keep in as natural condition as possible.
Germs are the cause of decomposition, Then, in order that fruit may keep, all the germs which have settled upon it from the surrounding air and from the touch of fingers, must be destroyed. Fruit does not harbor as many germs as most foods; this is on account of the acids which they contain. But in handling the fruit after the skin is removed, germs from the air will adhere and prevent its keeping, unless they are destroyed.
Another reason why fruit sometimes spoils, is because the germs that are in the empty cans are not all killed. This is the only reason why new cans will keep fruit better than old ones. When using old cans, they should be thoroughly sterilized. As soon as the fruit is taken out, the cans should be thoroughly washed, scalded in boiling water, then drained, by inverting and resting one edge on something to allow the steam to escape, and stored away without the covers on. The covers should be well cleansed so that all fruit be removed from every crease, and put away in a box in a dry place; the rubbers should be tied with a string and kept where it is warm, as freezing injures the rubbers. The practise of putting the rubber in the can and screwing on the cover is not to be recommended, as the air confined in the can decomposes. When cans are well taken care of, as previously described, they need only thorough washing and rinsing when they are needed for canning.
Only the best fruit is good enough to can. Partially decayed fruit is expensive at any price, as it is almost sure to spoil. Fruit spoils in different ways. Sometimes it ferments, becoming foamy, and begins to ooze out. This can be readily told by the looks; but again it will look all right, when the fruit has changed to vinegar; then sometimes it will have a musty taste. In any of these cases, it is unfit to use. Many whose sense and taste are not very acute do not detect the difference between good and spoiled fruit, and then can not understand why their stomachs give them so much trouble.
In canning fruit, it is usually best to put the fruit in before it is cooked. This is especially true of small fruits; as, strawberries, plums, etc. Indeed, all fruit looks a great deal better canned in this way.
Fill the cans full, and shake down as much as possible, then fill with a very thin syrup, put on the covers, but not the rubbers, and cook in a boiler with enough water nearly to cover the cans. Different fruits require different lengths of time for cooking. Strawberries only require twenty minutes after the water begins to boil. Pears, if they are hard, take two hours. When done, fill up with syrup, put on the rubber, and screw down tight. Invert to see if it is air-tight, and then set, with the cover down, on the table to cool. When cold, turn over, and tighten the covers if possible; and if it is fruit which fades, as strawberries, the can should be wrapped with brown paper, and then set in a dark, cool place. All fruit is better to be kept in a cool place.