Extension Logo
Extension Logo
University of Minnesota Extension
https://extension.umn.edu

Vegetable blanching directions and times for home freezer storage

Blanching pot.

Blanching is a must for most vegetables to be frozen. It slows or stops the enzyme action which can cause loss of flavor, color and texture.

The blanching time is very important and varies with the vegetable and size. 

  • Underblanching stimulates the activity of enzymes and is worse than no blanching.
  • Overblanching causes loss of flavor, color, vitamins and minerals.

Blanching directions

  1. Wash, drain, sort, trim and cut vegetables.
  2. Use 1 gallon water per pound of prepared vegetables or 2 gallons water per pound leafy greens.
  3. Put vegetables into blancher (wire basket, coarse mesh bag or perforated metal strainer) and lower into boiling water.
    • Or steam blanch: boil 1-2 inches of water in a pot, bring to boil and then put a single layer of vegetables in basket.
  4. Cover. Start counting blanching time as soon as water returns to a boil.
    • Or if steam blanching, start counting immediately.
  5. Keep heat high for the time given in the directions.
  6. Cool immediately in ice water or cold water (60 degrees F or below) for the same time used in blanching (except for corn-on-the-cob for which cooling time is twice the time of blanching). Stir vegetables several times during cooling.
  7. Drain vegetables thoroughly.
  8. Pack the vegetables either by dry-pack or tray-pack.
    • Dry-pack: Pack vegetable tightly into containers or freezer bags. Press out air and seal tightly.
    • Tray-pack: Put a single layer of the vegetable on a shallow pan and put the pan into the freezer. As soon as the vegetable is frozen, put them into a freezer bag or container. Press out air and seal tightly.
  9. Freeze.
  10. Frozen vegetables will maintain high quality for 8 to 12 months at zero degrees F or lower.

Vegetable blanching times (water blanching)

Different vegetables and the amount of time needed for blanching in boiling-water or steam.
Vegetable Blanching In boiling water (minutes) Blanching in steam (minutes)
Asparagus Small stalk 2 3
Asparagus Medium stalk 3 5
Asparagus Large stalk 4 6
Beans - snap, green or wax 3 5
Beans - lima, butter or pinto Small 2 3
Beans - lima, butter or pinto Medium 3 5
Beans - lima, butter or pinto Large 4 6
Broccoli - flowerets 1 1/2 inches across 3 5
Brussels sprouts Small heads 3 5
Brussels sprouts Medium heads 4 6
Brussels sprouts Large heads 5 7
Cabbage or Chinese cabbage Shredded 1 1/2 2 1/2
Carrots Small, whole 5 8
Carrots Diced, sliced or strips 2 3
Cauliflower - flowerets 1 inch 3 5
Celery 3 -
Corn - corn-on-the-cob Small ears (cooling time is twice the time of blanching) 7 10
Corn - corn-on-the-cob Medium ears (cooling time is twice the time of blanching) 9 13
Corn - corn-on-the-cob Large ears (cooling time is twice the time of blanching) 11 16
Corn - whole kernel or cream style Ears blanched before cutting corn from cob. (cooling time is twice the time of blanching) 4 6
Eggplant 4 6
Greens - collards 3 5
Greens - all other 2 3
Kohlrabi Whole 3 -
Kohlrabi Cubes 1 -
Mushrooms Whole - 9
Mushrooms Buttons or quarters - 9
Mushrooms Slices - 5
Okra Small pods 3 5
Okra Large pods 5 8
Onions (blanch until center heated) 3-7 -
Onions Rings 10-15 seconds -
Peas - edible pod 2-3 4-5
Peas - green 1 1/2 - 2 1/2 3-5
Peppers - sweet Halves 3 5
Peppers - sweet Strips or rings 2 3
Potatoes - Irish (new) 3-5 5-8
Rutabagas 3 5
Soybeans - green 5 -
Squash - summer 3 5
Turnips 3 5

Carol Burtness, former Extension educator and Suzanne Driessen, Extension educator

Reviewed in 2018

Share this page:

© 2018 Regents of the University of Minnesota. All rights reserved. The University of Minnesota is an equal opportunity educator and employer.