Add Yahoo as a preferred source to see more of our stories on Google. We use strawberry jam as an example to explore the underlying principles of water activity, a key technique for food preservation.

Jam is the sweet, spreadable result of combining mashed fruit, sugar, and an acid, such as lemon juice. Jam may also contain salt to balance the sweetness and pectin, a naturally occurring fiber found ...

Jam is not terribly difficult to make. Although it’s easy to overthink the process, just keep in mind that jam essentially has one goal: to preserve fruit at the height of its season so that you can ...