Concord grapes must have their inedible seeds removed before making juice, jam or eating. The distinctive flavor of Concord grapes sets these apart from seedless varieties of grapes, and the time it takes to remove the seeds will be worth the effort. Concord grapes are easily squeezed from their skins, known as slip-skin, says the Concord Grape Association. This differentiates these grapes from other dark purple grapes.
Wash the grapes under running water to remove dirt and residue.
Hold a grape between your thumb and forefinger. Squeeze gently so the grape slips out of its skin. Discard the skin and set aside the grape. Repeat with the remaining grapes.
Remove the seeds from the grapes for eating the whole fruit. Cut the grapes in half and dig out the seed from each grape for using in recipes.
Puree the grapes and remove the seeds for juicing or use in jelly. Set a sieve over a bowl to catch the seeded puree. Force the skinned grapes through a sieve to separate the seeds and use the puree in your recipes. Discard the grape seeds.