Frozen grapes are best if used between 10 and 12 months. Although they are best when used within a year of freezing, frozen grapes kept frozen at 0-degrees Fahrenheit are safe to eat indefinitely.
Frozen grapes are a tasty, cold treat. Red grapes freeze perfectly to be eaten frozen while green grapes freeze hard and solid. Remove from vines, wash and let air dry before freezing. To prevent the grapes from freezing together in clumps, put them in a single layer on a flat cookie sheet and freeze for a few hours before transferring to an airtight bowl of freezer bag.