3	qts.	fresh or frozen blackberries
4	cups	water
3	cups	sugar
1	tbsp.	whole cloves
1	tbsp.	whole allspice
2		cinnamon sticks (4 inches) - (broken)
2	bottles	diet lemon-lime soda (2 liters each)

Crush blackberries in a large kettle. Add water and bring to a boil. Reduce heat to medium and cook for 10 minutes. Strain through a jelly bag, reserving juice and discarding pulp. Add water to juice if necessary to equal 2 quarts; pour into a large kettle. Slowly stir in sugar until dissolved. Place spices in a cheesecloth bag; add to juice. Simmer, uncovered, for 30 minutes. Bring to a boil; remove spice bag and discard. Pour hot into hot jars, leaving ¼-inch headspace. Adjust caps. Process for 15 minutes in a boiling water bath. To serve, mix two parts soda to one part concentrate.

Yield: 48 servings (4 pints concentrate)