• When possible, preserve fresh, locally-grown grapes for the best quality and nutritional value.
• Know when fresh grapes are available in your state with this seasonal food guide.

• If this is your first time freezing or it has been awhile, it is recommended that you read General Freezing Information before beginning.  

1. Selection & Ingredients

• Select fresh, mature, firm fruit. Do not use fruit that show signs of decay or mold.
• Approx. 4 pounds of grapes will yield one quart container
• Anti-darkening treatment:  
  • Ascorbic acid (Vitamin C) –or-
  • Commercial ascorbic acid mixture (follow manufacturer’s directions for treating fruit)
• Sugar for sugar or syrup pack (optional)
  • NOTE: Unsweetened, dry packed fruits will lose quality faster than those packed in sugar or syrup.

2. Equipment

• Cooking pot (if using liquid pack method)
• Colander
• Cutting board
• Knife
• Ruler/headspace tool
• Use clean packing containers and materials that are moisture and vapor-proof/resistant:
• Rigid containers (glass jars and hard plastic containers) are especially good for freezing foods with liquid. Covers for rigid containers should fit tightly.
  • Square or rectangular, straight-sided rigid plastic containers make the best use of freezer space.
  • Wide-mouth, dual-purpose glass jars made for canning and freezing are tempered to withstand extremes in temperature and allow for easier removal of partially-thawed foods.
  • Narrow-mouth dual-purpose glass jars can also be used but require greater headspace (to avoid expansion breakage at the shoulder) and foods must be completely thawed before removal.
• Flexible bags or wrappings (plastic freezer bags, freezer wrap or paper, and heavyweight aluminum foil) are best for freezing food products with little or no liquid.
  • Vacuum packaging removes more oxygen than other freezing methods (Refer to manufacturer's instructions.)

3. Prepare Equipment 

• Before use, wash containers in hot soapy water and rinse well. Dry.

4. Prepare Fruit 

• Thoroughly stem, sort, and wash grapes.
• Leave seedless grapes whole. Cut grapes with seeds in half and remove seeds.

5. Pack

Choose one of the following packing methods:

Unsweetened (Dry) Pack-

• To prevent darkening of cut grapes, dissolve 1/4 teaspoon (750 mg) ascorbic acid in ¼ cup cold water for each quart of fruit. Sprinkle over the fruit.
  • If using commercial ascorbic acid mixture, follow manufacturer’s directions.
• Pack grapes tightly into containers, leaving proper headspace for the container type (see Headspace table below).
  • Whole grapes can also be frozen first on a tray and then packed into containers as soon as they are frozen.
• Before sealing, make sure sealing edges are free of moisture or food.
  • If using flexible bags or wrap, remove as much air as possible.
• Seal.

Syrup (Liquid) Pack-

• A 20% sugar syrup is recommended for grapes
  • Lighter syrups (10-20%) are lower in calories and desirable for mild-flavored fruits, such as melons.
  • Heavier syrups (30-50%) may be needed for very sour fruits.
  • Plan for 1/2 to 2/3 cup syrup for each pint of fruit.
• To make the syrup, dissolve sugar in lukewarm water, mixing until the solution is clear (see Sugar Syrup Recipe table below).
  • Cool syrup before using. (Syrup can also be prepared the day before and refrigerated until ready to use.)
• To prevent browning, add 1/2 teaspoon (1500 mg) ascorbic acid to each quart of cooled syrup.
  • If using commercial ascorbic acid mixture, follow manufacturer’s directions.
• Add 1/2 cup syrup/pint container or 1 cup syrup/quart container.
• Add sliced grapes, pressing down firmly, and cover with additional syrup, as needed, leaving the proper headspace for the container type (see Headspace table below).
  • If using rigid containers, place a small piece of crumpled water-resistant paper on top to hold fruit down.
  • If using flexible bags, remove as much air space as possible.
• Before sealing, make sure sealing edges are free of moisture or food.
• Seal.

Sugar Syrup Recipes

% Syrup	Sugar (cups)	Water (cups)	Yield      (cups syrup)
10	1/2	4	4 1/2
20	1	4	4 3/4
30	1 3/4	4	5
40	2 3/4	4	5 1/3
50	4	4	6

 

Headspace for Freezing Fruits

Pack Type	Container with wide top opening		Container with narrow top opening		Flexible bags and wraps
	Pint	Quart	Pint	Quart	Any Size
Liquid Pack	½ inch	1 inch	¾ inch	1 ½ inches	Remove as much air as possible
Dry Pack	½ inch	½ inch	½ inch	½ inch	Remove as much air as possible

 

6. Store

• Freeze packaged fruits as quickly as possible to 0°F or below.
  • For quickest freezing, place containers in single layer in freezer.
• Label with the name of food, date, and type of pack.
• Most fruits will maintain high quality for 8-12 months at 0°F or below.