• When possible, preserve fresh, locally-grown rhubarb for the best quality and nutritional value. Determine when fresh rhubarb is available where you live 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.