Homemade grape juice concentrate made from fresh Concord grapes with no added sugar. The fresh juice is strained and gently reduced by half for a rich grape concentrate that can be refrigerated or frozen.
Cook and mash: Remove the grapes from their stems and wash well. Place in a heavy-bottomed pot with ½ cup water and bring to a boil. Mash the softened grapes with a potato masher, reduce the heat, and simmer for about 10 minutes.
Strain and chill: Pour the cooked grapes through a fine mesh strainer, gently working the pulp with a spoon to extract the juice. Strain again, cover, and refrigerate overnight.
Strain and reduce: The following day, strain the chilled juice once more. Measure 4 cups into a wide, heavy-bottomed saucepan and simmer uncovered over medium-low heat until reduced to approximately 2 cups.
Cool and store: Cool the concentrate and transfer it to a clean container. Refrigerate for short-term use or divide among freezer-safe containers and freeze for longer storage.
Notes
Sweetness: No sugar is added. Reducing the juice concentrates its naturally occurring sugars as well as its tartness, so flavor will depend on the grapes you started with.Reduction: Use volume rather than cooking time to determine when it's finished. Your goal is to reduce 4 cups of strained juice to approximately 2 cups.Straining: I prefer a fine mesh strainer because it allows me to extract plenty of juice from the cooked grapes. Straining again after the overnight rest removes additional sediment and tartrate crystals.Freezing: Leave adequate room for expansion in freezer containers. Smaller portions are convenient for thawing as needed.To reconstitute: Start with equal parts concentrate and water and adjust to taste.