Michigan State University Extension
Preserving Food Safely - 01600300
2 cups crushed strawberries or blackberries (about 1 quart berries) 4 cups sugar 1 package powdered pectin 1 cup water
Sort and wash fully ripe berries. Drain. Remove caps and stems; crush berries.
Place prepared berries in a large mixing bowl. Add sugar, mix well and let stand for 20 minutes, stirring occasionally.
Dissolve pectin in water and boil for 1 minute. Add pectin solution to berry-and-sugar mixture; stir for 2 minutes.
Pour jam into freezer containers or canning jars, leaving 1/2 inch space at the top. Cover containers and let stand at room temperature for 24 hours or until jam has set. Label and freeze. Store up to 4 weeks in the refrigerator after opening. Makes 5 or 6 half-pint jars.