We typically list fruits and their juices as the same ingredient in Cocktail Party; if you have a lemon, we assume you have lemon juice, and so on. Grape juice is an exception, because the flavor and texture of the stuff in the bottle is often radically different from fresh grapes, and because it’s generally called for in larger measures, while whole grapes are typically called for to be muddled and will produce less juice.
If you have a lot of grapes, don’t mind juicing them, and want them to count towards recipes that call for “grape juice” specifically, go ahead and check off this ingredient too.
