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Extension > Food > Food Safety > Preserving and Preparing > Vegetables and Herbs > How to Prepare Vegetables for Freezing

Vegetables and Herbs

How to Prepare Vegetables for Freezing

William Schafer, Food Technologist — Department of Food Science and Nutrition

Reviewed 2012 by Suzanne Driessen, Extension Educator — Food Safety.

VEGETABLES PREPARATION
Asparagus

Pick bright colored brittle stalks that snap when broken and have tight heads.

Wash and sort medium and large stalks. Discard woody and blemished stalks. Break off fibrous ends. Leave whole or cut in 1- to 2-inch lengths. Blanch medium stalks 3 minutes, large stalks (½- to ¾-inch diameter) 4 minutes. Chill in ice water. Asparagus has a shorter storage life than other frozen vegetables. Should be used within 9-10 months.
Beans (Green and Yellow Podded)

Pick young tender beans that snap when broken. Harvest while seeds are small and tender.

Wash, snip off tips and sort for size. Cut or break into suitable pieces or freeze small beans whole. Blanch 3½ minutes. Chill in ice water.
Beans, Lima

Pick well-filled pods containing green, young tender beans (white beans are overmature).

Wash, shell and sort. Blanch small and medium beans, 3 minutes; large beans, 4 minutes. Chill in ice water.
Beans, Snap (Italian) Wash, snap off ends and cut or break into l - or 1½-inch lengths. Blanch 3½ minutes. Chill in ice water.
Beets

Use garden varieties of good color and quality. Pick smooth, tender small to medium beets.

Remove tops leaving 2 inches of top and wash. Cook until tender. Chill. Remove skins. Slice or dice large beets.
Broccoli

Choose firm, tender stalks with bright green compact heads.

Discard off-color heads or any that have begun to blossom. Remove tough leaves and woody butt ends. Cut through stalks lengthwise, leaving heads 1 inch in diameter. Soak ½ hour in salt brine (½ cup salt to 1 quart water) to drive out small insects. Rinse and drain. Blanch 4 minutes in water. Steam-blanch 5 minutes. Chill in ice water. Pack heads and stalks ends alternately in container. Broccoli may be cut into chunks or chopped.
Brussels Sprouts

Pick firm, compact heads of good green color.

Wash and trim. Soak ½ hour in salt brine (see broccoli). Rinse and drain. Blanch medium heads, 4 minutes; large heads, 5 minutes. Chill in ice water.
Carrots

Pick smooth, tender carrots before roots become woody. Harvest in cool weather.

Top, wash and scrape. Dice or slice ¼-inch thick. Blanch 3½ minutes. Chill in ice water.
Cauliflower

Use well-formed, compact heads with fresh leaves.

Trim and wash. Split heads into individual pieces 1 inch in diameter. Soak ½ hour in salt brine (see broccoli). Rinse and drain. Blanch 4 minutes. Chill in ice water.
Sweet Corn—On-the-Cob

Use Golden Bantam types. Small to medium ears are preferred. Harvest early in the morning if weather is hot. If corn is immature, it is watery when cooked; if too mature, it is doughy. Process rapidly.

Husk, remove silks and trim ends. Use a large kettle (12- to 15-quart capacity) for blanching. Chill in ice water. Corn which is not thoroughly cooled may become mushy. The long blanching time is necessary to inactivate enzymes which are in the cob. The long cooling time is needed to chill the cob. Failure to follow the blanching and freezing times will result in the development of cobby off-flavors.
Blanching Time—12 Quarts Water

Size of ears Number
ears
Diameter
(inches)
Blanch
(minutes)
Cooling
time
(minutes)

Midget 24 1¼ or less 8 16
Small 14 Between 1¼
and 1½
8 16
Medium to
large
10 Over 1½ 11 22
Sweet Corn—Cut Husk, remove silks and trim ends. Use a large kettle (12- to 15-quart capacity). Blanch whole kernel corn to be cut from the cob 4½ minutes.
Eggplant

Use garden varieties of good color and quality.

Precooked eggplant is usually more satisfactory for freezing than blanched eggplant. Peel, cut into ¼ to 1/3-inch slices, or dice. To retain light color, drop pieces immediately into cold water containing 4 tablespoons salt per gallon. Blanch 4½ minutes. Chill and package in layers separated by sheets of freezer paper.
Garden Herbs Wash and drain, but do not blanch leaves. Wrap a few sprigs or leaves in foil or seal in film bags. Store in carton or glass jar.
Kohlrabi

Choose young, tender kohlrabi.

Cut tops, wash, peel and dice in ½-inch cubes. Blanch 2½ minutes. Chill in ice water.
Mushrooms

Pick young firm mushrooms of edible types.

Wash and remove stem base. Freeze small mushrooms whole; cut large ones into 4 or more pieces. When blanching mushrooms, add 1 teaspoon citric acid (or 3 teaspoons lemon juice or ½ teaspoon ascorbic acid) per quart of water to prevent darkening. Blanch medium or small whole mushrooms 4 minutes; cut pieces, 3 minutes. Chill. OR: Slice mushrooms ¼-inch thick. Saute in butter, 2 minutes. Cool.
Onions

Sweet Spanish types preferred. Can use good garden varieties.

Peel onions, wash and cut into quarter sections. Chop. Blanch 1½ minutes. Chill in ice water. (They will keep 3-6 months.)
Peas (Green, English)

Avoid Alaska (smooth skin) and other starch peas. Pick bright green, crisp pods with tender, sweet peas but not overmature.

Wash, shell small amount at a time. Blanch 1½ to 2 minutes. Blanch black-eyed peas 2 minutes. Chill in ice water.
Peas (Edible, Podded, Sugar or Chinese)

Select bright green, flat tender pods.

Wash. Remove stems, blossom ends, and any string. Leave whole. Blanch 2½ to 3 minutes. Chill in ice water,
Peppers (Green)

Choose crisp, well developed peppers of deep green color.

Wash, cut out stem and remove seeds. Halve, slice or dice. Blanch halved peppers, 3 minutes, sliced or diced ones, 2 minutes. Chill in ice water. You can freeze chopped peppers without blanching them.
Peppers (Pimiento)

Choose crisp, well developed peppers of deep red color.

Oven roast at 400° F for 3 to 4 minutes. Cook, skin and pack dry without additional heating.
Potatoes

Any good quality potato. For french fries, a russet type preferred.

Wash, peel, remove deep eyes, bruises and green surface coloring. Cut in ¼- to ½-inch cubes. Blanch 5 minutes. Cool. For hash browns: Cook in jackets until almost done. Peel and grate. Form in desirable shapes. Freeze. For french fries, peel and cut in thin strips. Fry in deep fat until very light golden brown. Drain and cool.
Pumpkin

Select any good pie pumpkin of good color.

Cut or break into fairly uniform pieces. Remove seeds. Bake at 350° F, or steam until tender. Cool, scoop pulp from rind, and mash or put through ricer. You can prepare pie mix for freezing, but omit cloves.
Spinach and other Greens

Select young, tender leaves.

Sort and remove tough stems. Wash. Blanch most leafy greens 2 minutes. Blanch collards and stem portions of Swiss chard 3 to 4 minutes. Blanch very tender spinach 1½ minutes. Chill in ice water.
Summer Squash—Zucchini

Select when 5-7 inches long and rind tender and seeds small.

Wash, peel and cut in pieces. Blanch ¼-inch slices, 3 minutes; 1½-inch slices, 6 minutes. Chill in ice water. If skin is tender, you do not need to peel.
Winter Squash

Select squash with shells hard enough so you cannot push thumbnail through them. "Dry" types are recommended.

Prepare same as pumpkin. You can blend two or more varieties or blend squash with pumpkin.

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