State University Extension
Preserving Food Safely - 01600548
1. Always use the full amount of sugar called for in the
recipe. Reducing the amount of sugar may prevent the jam
from setting up.
2. Always prepare only one batch of jam at a time.
Doubling the recipe may prevent the jam from setting up.
3. Always use fresh, ripe fruit. As fruit becomes over-
ripe, its natural pectin content decreases and the gelling
ability of the fruit is reduced.
4. Finely chop all fruits used for making jams, but do not
puree them. Pureed fruit will add too much liquid and too
much fruit for a good gel.
5. Use only the type of pectin called for in a recipe.
Liquid or powdered pectin may be used, but they may not be
substituted for each other.