Michigan State University Extension
Preserving Food Safely - 01600322
QUANTITY: An average of 14 pounds is needed per canner load of 7 quarts; an average of 9 pounds is needed per canner load of 9 pints. A lug weighs 26 pounds and yields 12 to 14 quarts of whole grapes--an average of 2 pounds per quart.
QUALITY: Choose unripe, tight-skinned, preferably green seedless grapes harvested two weeks before they reach optimum eating quality.
PROCEDURE: Stem, wash and drain grapes. Prepare very light, or light syrup (see directions below).
Hot pack--Blanch grapes in boiling water for 30 seconds. Drain and proceed for raw pack.
Raw pack--Fill hot jars with grapes and hot syrup, leaving 1-inch headspace.
Adjust lids and process.
Very Light Syrup Mix 6-1/2 cups water to 3/4 cups sugar for 9 pint or 4 quart load. Mix 10-1/2 cups water and 1-1/4 cups sugar for 7 quart load. Heat sugar and water to boiling.
Light Syrup Mix 5-3/4 cups water to 1-1/2 cups sugar for 9 pint or 4 quart load. Mix 9 cups water and 2-1/2 cups sugar for 7 quart load. Heat sugar and water to boiling.
RECOMMENDED PROCESS TIMES FOR GRAPES, WHOLE IN A BOILING-WATER CANNER
Process Time at Altitudes of Style of Jar 0- 1001- 3001- over Pack Size 1000 ft. 3000 ft. 6000 ft. 6000 ft.
Hot Pints 10 min. 15 min. 15 min. 20 min.
Hot Quarts 10 15 15 20
Raw Pints 15 20 20 25 Raw Quarts 20 25 30 35