Jam is the product obtained by cooking sugar with fruits or vegetables. In the process of making jam, the fruits or vegetables are somewhat crushed, the object being to cook the mass into a smooth paste of a jelly-like consistency.
Use three-quarters ripe fruit and one-quarter slightly under-ripe fruit in making jam. This will give flavor and color to the product and improve the consistency. Whole fruit is used to better advantage, but cut or bruised fruit (not decaying) may also be used.
SUGAR:
Use any sugar of good quality, except brown or maple sugar.
HEAT:
Any heat produced by a cook stove can be used. Do not cook jam in the open air.
EQUIPMENT:
Kettles: Use any good sized kettle-porcelain lined, agate or copper kettles preferred.
Spoons: Use wooden spoons or spatulas. Do not use metal spoons.
Scales: Use ordinary kitchen scales and weights.
Glasses, Jars and Containers: Use jelly glasses, glass jars or other containers with tightly fitting covers.
Paraffin: Any paraffin of good quality will do.
Proportions for Making Jam:
There is practically only one recipe used in making jam:
1 pound of fruit, washed and picked
3/4 pound of sugar
Fruits vary in sugar content, but, by cooking them with the sugar in making jam, the amount of sugar in the mass will be equalized.