Commonly Asked Questions
What creates foam when cooking jam and jelly mixtures? Why is it important to remove foam?
Foam is simply air trapped in the sugar solution. If not removed, the air bubbles trapped inside increase the amount of air within a sealed jam or jelly jar, which may shorten the life of the product.
Can sweetener be substituted for sugar?
Sugar is necessary for safe preservation in tested recipes. Do not reduce the amount of sugar or replace it with sugar substitutes.
Are low- or reduced-sugar recipes available?
Low-sugar recipes may be found on packages of low-sugar pectin or on the National Center for Home Food Preservation's website. For reduced-sugar preserves, purchase pectins sold specifically for making reduced- or no-sugar-added jams and jellies.
Is it better to use powdered or liquid pectin?
Pectin is commercially available in both liquid and powdered forms; however, recipes are specific in the type of pectin used. Only use the type of pectin indicated.
If fresh fruit is unavailable, are there other options for making jellied fruit products?
Commercially canned or frozen fruit may be used to make jellied products. Since they are made from fully-ripe fruit, which contains lower levels of pectin than under-ripe fruit, pectin must be added.
- Select commercially canned or frozen products without added sugar.
- Select fruits canned in their own juice.
If the top half-inch or so of a light-colored jam darkens over time, is it safe to eat?
Lighter fruits, such as peaches, are more prone to darkening. If no other signs of spoilage or damage to the product's jar or lid can be seen, darkening of the top half inch or so of a light-colored jam is not a safety concern.