This grape juice recipe instructs you how to make your own grape juice. The best grapes for juice are concords. Juice can be refrigerated or even frozen in plastic containers.
Wash grapes thoroughly, leaving out old shriveled grapes, and ones that aren't ripe. Put grapes into a large bowl, and mash up with a potato masher.
Put mashed grapes into a large pot, and bring to a simmer on medium heat. Let simmer for 10 minutes stirring occasionally so grapes don't stick to bottom of pot. About 5 minutes in mash again to break up more of the grapes.
With another large pot, and a fine metal sieve, strain grapes into new pot. Let grapes strain out overnight in fridge.
Toss out skins, sediment will form on bottom of pot, so you can strain again to remove some of the sediment. Serve and enjoy.