Concord Grape Jelly

Ingredients

Instructions

1. 1Wash 6 half-pint jars in hot soapy water, rinse well, and boil them in a canner or large pot of water for 10 minutes to sterilize, since this jelly processes for less than 10 minutes; keep jars hot until filling time.
2. 2Simmer the new lids in hot (not boiling) water per the manufacturer's directions and keep warm.
3. 3Wash the screw bands in warm soapy water and set aside.
4. 4If using fresh grapes, wash and stem 4 pounds of Concord grapes, place in a large pot with 1/2 cup water, crush slightly, cover, and simmer for 10 minutes until soft; strain through a dampened jelly bag or cheesecloth for at least 2 hours without squeezing to yield 4 cups of clear juice, then refrigerate the juice overnight and strain again to remove tartrate crystals if any have formed.
5. 5Measure exactly 4 cups of grape juice (fresh-extracted or bottled unsweetened) into a large saucepot and stir in the full box of powdered pectin.
6. 6Bring the mixture to a full rolling boil over high heat, stirring constantly, then add all 7 cups of sugar at once.
7. 7Return to a full rolling boil that cannot be stirred down and boil hard for exactly 1 minute, stirring constantly.
8. 8Remove from the heat and skim off any foam.
9. 9Ladle the hot jelly into the hot, sterilized jars, leaving 1/4 inch of headspace.
10. 10Remove air bubbles with a non-metallic spatula, wipe the rims clean, center a warm lid on each jar, and screw on a band until fingertip tight.
11. 11Process in a boiling-water canner, jars covered by 1 to 2 inches of water, for 5 minutes for half-pints and 5 minutes for pints, timing from when the water returns to a full rolling boil.
12. 12Adjust for altitude: add 5 minutes at 1,001-3,000 feet, 10 minutes at 3,001-6,000 feet, 15 minutes at 6,001-8,000 feet, and 20 minutes above 8,000 feet.
13. 13Turn off the heat, wait 5 minutes, then remove jars to a towel-lined counter and let cool undisturbed for 12 to 24 hours.
14. 14Check the seals (concave, firm lids), remove the bands, wipe the jars, and label with contents and date.
15. 15Store in a cool, dark place up to 1 year for best quality; refrigerate after opening and use within about 3 weeks.
16. 16Do not alter the ratio of juice, sugar, and pectin, as this balance determines both the safety and the set of the jelly.