Many think that if fruit is stirred while cooking, it won’t give you as clear a jelly like it would if you just let it cook, but so many cooks disagree on this point, and each jelly maker can decide this matter for their own self.
Jelly made from dripped juice doesn’t need to be clearer than what’s made from juice taken under pressure, especially if it’s allowed to stand and settle before being made into jelly.
While it’s unnecessary, a small amount of water, (one cup to six quarts of fruit) could be added to grapes or berries to help extract the juice. Water that barely covers the fruit is a necessity when dealing with firm fruit like apples. When apples are plenty, apple juice can be used as the liquid to cook the pulp of some other choice fruit after the first extraction by the way.
When water is used, the flavor is less than at the first extraction, the quantity of pectin present is probably below the normal, and the proportion of sugar must be lessened. Pectin and sugar must be proportioned accurately, if you want the best results.
The cleaner the fruit, the brighter and clearer the jelly will be. Jelly is brighter and better when the addition of the sugar is delayed until the water has been evaporated. Heating the sugar on the stove will improve the jelly. Honey may replace sugar in whole or part in jelly making.
Jelly should always be made in small quantities. If two quarts of juice is used, let it in two saucepans because long cooking darkens the product. If jelly poured into glasses doesn’t seem firm enough, set the glasses in the sun, cover them with a pane of window glass or glass lids from fruit jars for two or three days.