6 c. prepared fruit (about 4 lbs. ripe grapes)
1 box powdered fruit pectin
7 1/2 c. (3 1/4 lbs.) sugar

First, prepare the fruit. Slip skins from about 4 pounds ripe Concord or loose-skinned grapes. Set aside.

Add 1 cup water to pulp. Bring to a boil; cover and simmer 5 minutes. Press through a sieve to remove the seeds. Chop or grind skins; add to pulp. Measure 6 cups into a very large saucepan.

Then make the jam. Add powdered pectin to fruit in saucepan and mix well. Bring to a hard boil over high heat, stirring constantly. At once stir in sugar. Bring to a full rolling boil and boil hard 1 minutes, stirring constantly.

Remove from heat and skim off foam with metal spoon. Then alternately stir and skim for 5 minutes to cool slightly and to prevent floating fruit. Ladle quickly into glasses. Cover jam at once with 1/8 inch hot paraffin. Makes 6 1/2 pounds of jam, or enough for 13 medium glasses.

SPICED GRAPE JAM:

Prepare Grape Jam as directed, adding 1/4 to 1 teaspoon each cinnamon, ginger, and allspice or any desired combination of spices, to grapes before simmering.