2954—Jams

Under this generic title the following preparations are classed:—

(1) Those in which the fruit is treated directly with the sugar:—

(2) Those in which the juice alone, owing to its gelatinous nature, produces, together with the sugar, consistent jellies.

The amount of sugar used is subject to the nature of the fruit and its sweetness; but in the case of nearly all tart fruits, the weight of sugar should equal that of the fruit, or nearly so.

If too much sugar be used, the flavour is impaired; while crystallisation will follow very shortly afterwards; if too little be used, the jam has to be overcooked in order to be made sufficiently consistent, and the flavour is once more impaired by protracted evaporation; finally if the time allowed for cooking be inadequate, rapid fermentation will be the result.

In making jam, therefore, the operator should base his measure of sugar upon the nature of the fruit he intends treating.