CHAPTER VI
JELLIES, JAMS, PRESERVES, MARMALADES, FRUIT JUICES AND SIRUPS
For jelly making select firm, slightly underripe fruit that is fairly acid and contains a large amount of pectin. Fruit that is just a little underripe contains more pectin than the mature or overripe fruits. Pectin is the substance that makes jelly harden. This fundamental jelly-making quality does not exist in all fruits. Such fruits as currants, crab apples and grapes contain much pectin and are, therefore, considered excellent jelly-making fruits.
The white inner skin of grapefruit is also a prolific source of pectin, but as it has a bitter taste we seldom use it for jellies, though we find it valuable in making orange, grapefruit and other marmalades.
Rhubarb, strawberries and cherries all lack pectin, but can be made into good jellies if we add the white skins of oranges and lemons to them while cooking.
So the very first thing we must know about jelly making is whether or not a fruit contains pectin. There will be no tears shed over jelly that will not "jell" if all young housewives will learn the simple test for pectin; to find out whether a juice contains pectin or not is a very easy matter.
Take one tablespoonful of grain alcohol—90 to 95 per cent.—and add to it one tablespoonful of cooked juice that has been cooled. The effect of the alcohol is to bring together the pectin in a jelly-like mass. If a large quantity of pectin is present it will appear in one mass or clot which may be gathered up on a spoon. You will notice I said cooked juice. It is peculiar that this pectin frequently is not found in the juices of raw fruits, though it is very plentiful in the cooked juices. Therefore the test must be made with cooked juice.
There is little pectin in the juice of raw apples, raw quince, raw grapes, and yet the cooked juices are full of pectin.
This test not only indicates the amount of pectin present, but it also gives some idea of the proper proportions of sugar to juice. If three-fourths or more of the juice forms a gelatinous mass or clot this indicates that you should use three-fourths as much sugar as juice. If the pectin is slightly gelatinous or is less than three-fourths of the whole volume of juice, use less sugar. If the pectin is less than one-half add some form of pectin to make the jelly, or can the juice for use as a beverage, for flavoring ice cream or some form of cooking.