Canning Recipes Canning Jars from Amazon Blackberry Jam Without Added Pectin Ingredients: Amount Measure Ingredient -- Preparation Method Cooking Directions: -------- ------------ -------------------------------- 4 cups crushed blackberries 4 cups sugar To prepare fruit. Sort and wash berries. Crush the berries. Put very seedy blackberries through a sieve or food mill. To make jam. Measure crushed berries into a kettle. Add sugar and stir well. Boil rapidly, stirring constantly, to 9 degrees above the boiling point of water (221 degrees), or until the mixture thickens. Remove from heat; skim. Fill and seal containers. Process for 5 minutes in boiling water. Remove jars, cool and store. This recipe yields 4 half-pint jars. © 2008 canning-recipes.com As an Amazon Associate I earn from qualifying purchases.