FCS3-335
Most vegetables freeze very well. Fresh, tender vegetables right from the garden are best for freezing. Among the products easily frozen are some that are the most difficult to can—corn, peas, and green lima beans. Tomatoes lose their firm texture and become soft and flabby, as do salad vegetables, such as celery, lettuce, green onions, and radishes. Tomato juice can be frozen satisfactorily but is so easy to can that you probably won’t want to use premium freezer space for it. Vegetables high in starch content, such as potatoes and mature lima beans, do not freeze well. Over-mature vegetables do not freeze well either.
Washing is the first step in preparing most vegetables for freezing. Wash them thoroughly in cold water. Lift them out of the water because grit settles to the bottom of the pan. Sort vegetables according to size for heating and packing unless they are to be cut into pieces of uniform size. Broccoli and cauliflower may be soaked for 30 minutes in 1 tablespoon of salt per gallon of water to remove insects before blanching.
Vegetables for freezing must be blanched before packaging. With the exception of green pepper, vegetables maintain a better quality in frozen storage if they are heated before packaging.
Blanching slows or stops the action of enzymes that help vegetables grow and mature. After maturity, enzymes cause loss of flavor and color. If vegetables are not heated enough, the enzymes continue to be active during frozen storage. Then the vegetables may develop off-flavors, discolor or toughen, and lose nutritional value. Heating also wilts or softens vegetables and makes them easier to pack. Heating time varies with the vegetable and size of pieces.
The most satisfactory way to blanch most vegetables is in boiling water. Use a blancher, which has a blanching basket and cover, or fit a wire basket into a large kettle and add the cover. Using at least 1 gallon of boiling water for each pound of prepared vegetables, follow the blanching directions given for the vegetable you are freezing.
Broccoli, pumpkin, sweet potatoes, and winter squash can be either boiled or steamed. To steam, use a kettle with a tight lid and a rack that holds a steaming basket at least 3 inches above the bottom of the kettle. Put 1 or 2 inches of water in the kettle and bring the water to a boil. Put the vegetables in the basket in a single layer so that steam reaches all parts quickly. Cover the kettle and keep the heat high. Follow the directions given for the vegetable you are freezing.
| Recommended Blanching Times | Vegetable | Cut/Size | Blanching Time | Asparagus | Small stalks Medium stalks Large stalks |
2 minutes 3 minutes 4 minutes |
Beans, green or wax | Regular cut French cut |
3 minutes |
Beans, lima | Small Medium Large or Fordhook |
2 minutes 3 minutes 4 minutes |
Beets | Small Medium |
25-30 minutes 45-50 minutes |
Broccoli | Uniform stalk | 3 minutes | Brussels sprouts | Small heads Medium heads Large heads |
3 minutes 4 minutes 5 minutes |
Cabbage or Chinese cabbage | Medium wedges | 1½ minutes | Carrots | Diced or sliced Small whole |
2 minutes 5 minutes |
Cauliflower | 1-inch pieces | 3 minutes | Corn, whole kernel | 4 minutes | Corn-on-the-cob | Small ears Medium ears Large ears |
7 minutes 9 minutes 11 minutes |
Greens (beet, chard, kale, and mustard) | 2 minutes | Greens (collards and spinach) |
Tender leaves |
3 minutes 1½ minutes |
Okra | Small pods Large pods |
3 minutes 4 minutes |
Peas, green | Plump | 1½ minutes | Peas, sugar snap and snow | Small pods Large pods |
1½ minutes 2 minutes |
Pepper, green | Blanching optional |
After vegetables are heated, they should be cooled quickly and thoroughly to stop the cooking. Plunge the basket of vegetables immediately into a large quantity of cold water (60°F or below). Change the water frequently, or use cold running water or ice water. If ice is used, you’ll need about 1 pound of ice for each pound of vegetables. It will take as long to cool the food as it does to heat it. When the vegetables are cool, remove them from the water and drain thoroughly.
The number of pints of frozen vegetables from a given quantity of fresh vegetables depends on the quality, condition, maturity, variety, trim, and cut size. Yields given in the following table are approximate.
| Vegetable Yields | Vegetable | Fresh | Frozen | Asparagus | 1 crate (12 2-lb bunches) | 15 to 22 pt | Beans, lima (in pods) | 1 bu (32 lb) | 12 to 16 pt | Beans, green and wax | 1 bu (30 lb) | 30 to 45 pt | Beet greens | 15 lb | 10 to 15 pt | Beets (without tops) | 1 bu (52 lb) | 35 to 42 pt | Broccoli | 1 crate (25 lb) | 24 pt | Brussels sprouts | 4 qt boxes | 6 pt | Carrots (without tops) | 1 bu (50 lb) | 32 to 40 pt | Cauliflower | 2 medium heads | 3 pt | Chard | 1 bu (12 lb) | 8 to 12 pt | Collards | 1 bu (12 lb) | 8 to 12 pt | Corn, sweet (in husks) | 1 bu (35 lb) | 14 to 17 pt | Kale | 1 bu (18 lb) | 12 to 18 pt | Mustard greens | 1 bu (12 lb) | 8 to 12 pt | Peas | 1 bu (30 lb) | 12 to 15 pt | Peppers, green | 2/3 lb (3 peppers) | 1 pt | Pumpkin | 3 lb | 2 pt | Spinach | 1 bu (18 lb) | 12 to 18 pt | Squash, summer | 1 bu (40 lb) | 32 to 40 pt | Squash, winter | 3 lb | 2 pt | Sweet potatoes | 2/3 lb | 1 pt |
Package vegetables in suitable freezer containers. Vegetables that package loosely, such as asparagus, Brussels sprouts, cauliflower, corn-on-the-cob, and hot peppers, need no headspace. Tomato juice and sections, as well as sweet potatoes, need a 1-inch headspace. All other vegetables need a ½-inch head-space. Seal, label, and freeze immediately.
Prepared by Sandra Bastin, Ph.D., R.D., Extension Food and Nutrition Specialist