Blackberry Preserves

4 cups blackberries (about 1 1/4 pounds), rinsed
1/4 cup fresh lemon juice
Four 2-inch pieces lemon peel, pith removed
Five 2-inch pieces orange peel, pith removed
1 cup sugar

Place the blackberries, lemon juice, lemon and orange peel, and 1/4 cup water in a medium saucepan and bring to a boil over medium-high heat. Reduce heat to medium-low and simmer until the berries are soft -- 10 to 12 minutes. Remove the citrus peels and stir in the sugar. Increase heat to medium-high, and let the mixture return to a boil.

Cook, stirring frequently, until the preserves have jelled -- about 7 minutes. (To test, place a teaspoon of preserves on a cold plate and refrigerate for 2 to 3 minutes. If a skin forms and the shape holds when pushed with a finger, the preserves have jelled.) Pour into clean glass jars and let cool to room temperature. Store refrigerated for up to 3 weeks. Makes 1 1/2 cups