Jelly is most easily prepared from fruits which are rich in pectin and contain some acid. Unless pectin is contained in the fruit, the addition of sugar to fruit juice will not cause the juice to jelly. But jelly may be made from a fruit lacking in pectin, if it is combined with a fruit rich in pectin.

Certain fruits contain pectin, but are lacking in acid, hence are not good for jelly making. These fruits can be used for jelly, however, if acid is added.

SELECTION OF FRUITS FOR JELLY MAKING.—For jelly making, choose fruits which contain considerable pectin and some acid. The fruits should be fresh and not over-ripe. Some "green" fruits make fine jelly. Currant, crabapple, grape, apple, and plum are good jelly-making fruits.

If it is desirable to use a fruit containing little pectin, as strawberries, add a fruit rich in pectin, as currants. If about 10 per cent of the fruit which contain much pectin is added to the other fruit, the flavor of the foundation fruit is not much altered.

If it is desired to use a fruit containing pectin but deficient in acid, as sweet apple and quince, add tartaric or citric acid. Since the acidity of fruits varies, no definite quantity of acid can be stated. It has been suggested [Footnote 127: See University of Illinois Bulletin, "Principles of Jelly Making," p. 249.] that enough acid should be added to make the fruit juice about as acid to taste as good tart apples. At least one teaspoonful of acid is required for one quart of fruit juice. Dissolve the acid in the fruit juice, then taste the mixture. If necessary, add more acid to produce the acidity indicated above. Jelly may be prepared from strawberries, peaches, and pears by the addition of these acids, but the flavor is somewhat impaired.

The suggestion has been made also [Footnote 128: Idem, p. 25.] that the inner white portion of lemon or orange peel be used as a source of pectin with fruit deficient in pectin. Remove the yellow portion of the rind, put the white portion through a food chopper, and soak in water for several hours or overnight. Then cook slowly for several hours. Strain out the solid portion. Add the liquid to the fruit juice deficient in pectin and use for jelly making. The rind of lemons and oranges may be dried for use in jelly making. When desired for use, soak and cook as directed above.

GENERAL METHOD OF JELLY MAKING

Wash and pick over the fruit; remove the stems, but use the skin and seeds and thus retain as much of the fruit as possible. The skin of fruit usually adds color to jelly. If large fruit is used, cut it in pieces. Cook the fruit slowly in water. Use very little water for juicy fruits, such as currants and raspberries,—1 cupful of water to 4 or 5 quarts of fruit. Crush the fruits during cooking.

To cook large fruits requires water. A general proportion is half as much water, by measure, as prepared fruit. A little less water may be used for peaches and plums and a little more for winter apples. A fair estimate is 3 quarts of strained juice from 8 quarts of fruit and 4 quarts of water. If the quantity of juice is greater than this, it should be boiled down to 3 quarts before adding the sugar.

When the fruit is cooked until it is very soft, it is ready for straining. For straining, make a bag of double cheesecloth or flannel. Wring the jelly bag out of hot water and suspend it from a strong support. Pour the cooked fruit into the bag and let the juice drip into a bowl. If transparent jelly is desired, do not press the juice through the bag; let the juice drip for several hours or overnight.