Home canning jams, jellies, and other soft spreads is fun and satisfying. Soft spreads all contain four main ingredients (fruit, sugar, pectin, and acid), and they differ only in their consistency. The formation of a gel depends on the right amount of each of the main ingredients. If you understand the science of gelling, all your soft spreads will be a success.
Bastin, Sandra and Clouthier, Debbie, "Home Canning Jams, Jellies, and Other Soft Spreads " (2016). Family and Consumer Sciences Publications. 95.