• When possible, preserve fresh, locally-grown rhubarb for the best quality and nutritional value.
  • Know when fresh rhubarb is 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, firm, tender, well-colored stalks. Do not use stalks that show signs of decay or mold.
  • Use 2 pounds of rhubarb per quart container.
  • Ice 
  • Sugar for sugar or syrup pack (optional)
    • NOTE: Unsweetened, dry packed fruits will lose quality faster than those packed in sugar or syrup.

2. Freezing Equipment

  • Cooking pot (if using liquid pack method)
  • Colander
  • Bowl (for ice water)
  • Knife
  • Cutting board
  • 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 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 wash rhubarb.
  • Trim and cut into 1-2 inch pieces.
  • Heat in boiling water 1 minute to help retain color and flavor, if desired.
    • Cool promptly in cold water. 

5. Packing for Freezing

Choose one of the following packing methods:

Unsweetened (Dry) Pack-

  • Pack either raw or preheated/cooled rhubarb tightly into containers without sugar, leaving proper headspace for the container type (see Headspace table below).
  • 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 40% sugar syrup is recommended for most fruits
    • Lighter syrups (10-30%) are lower in calories and desirable for mild-flavored fruits, such as melons.
    • Heavier syrups (40-50%) 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.)
  • Add 1/2 cup syrup/pint container or 1 cup syrup/quart container.
  • Pack either raw or preheated/cooled rhubarb into containers. 
  • 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

Pack Type

Wide mouth containers

Narrow mouth containers (w/shoulder)

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. Storage

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