To make juice:
Remove the grapes from the stem, rinse with cold water. Place them in a large pot and cover them with boiling water. Heat slowly and simmer until the grapes are very soft. Strain through a jelly bag, or through several thicknesses of cheesecloth.
To ferment:
For every gallon of juice, add 2 cups organic sugar, and 1 cup whey. Mix well until sugar is dissolved. Using a funnel, pour into glass swing top bottles and ferment for 3 days on the counter. Refrigerate.
This will keep for months in the refrigerator and will get really fizzy.