Michigan State University Extension
Preserving Food Safely - 01600323
QUANTITY: An average of 24-l/2 pounds is needed per canner load of 7 quarts; an average of 16 pounds per canner load of 9 pints. A lug weighs 26 pounds and yields 7 to 9 quarts of juice--an average of 3-1/2 pounds per quart.
QUALITY: Select sweet, well-colored, firm, mature fruit of ideal quality for eating fresh or cooking.
PROCEDURE: Wash and stem grapes. Place grapes in a saucepan and add boiling water to cover grapes. Heat and simmer slowly until skin is soft. Strain through a damp jelly bag or double layers of cheesecloth. Refrigerate juice for 24 to 48 hours. Without mixing, carefully pour off clear liquid and save; discard sediment. If desired, strain through a paper coffee filter for a clearer juice. Add juice to a saucepan and sweeten to taste. Heat and stir until sugar is dissolved. Continue heating with occasional stirring until juice begins to boil. Immediately fill juice into hot sterilized jars, leaving 1/4-inch headspace. (Use the following directions for sterilizing pint and quart jars. Sterilization of half gallon jars is not necessary). Adjust lids and process.
Sterilization of Empty Jars
To sterilize empty jars, put them right side up on the rack in a boiling-water canner. Fill the canner and jars with hot (not boiling) water to 1 inch above the tops of the jars. Boil 10 minutes at altitudes of less than 1,000 feet. At higher elevations, boil 1 additional minute for each additional 1,000 feet elevation. Remove and drain sterilized jars one at a time as filled.
RECOMMENDED PROCESS TIMES FOR GRAPE JUICE IN A BOILING-WATER CANNER
Process Times at Altitudes of Style of Jar 0- 1001- over Pack Size 1000 ft. 6000 ft. 6000 ft.
Hot Pints 5 min. 10 min. 15 min. Hot Quarts 5 10 15
Hot Half-gallons 10 15 20