Pitted: The Plate Test

This story is a component of the feature “Seasons of Preserves: Stone Fruit,� which is part of a four-part series on preserving fruit at home called “L.A. in a Jar.�

Another stalwart of making jam is the “plate test,� in which you spoon some hot jam onto a frozen plate so the jam cools quickly and you can test its texture when it sets or cools to room temperature. Again, while this is necessary when making jellies and marmalades, it’s not for stone fruit jam since I will give you other ways to evaluate when your jam is finished cooking by sight and feel that doesn’t dirty other dishes or have you swinging hot jam back and forth between the stove and freezer.