Most vegetables should be blanched before drying.
Blanching results in a higher quality product with better colours and storage life; evidence-based research shows that it also increases food safety, as some nasties have been shown to survive both the heat-drying process and the low-water activity afterwards.
Note that recommended blanching times for freezing vegetables will often differ from blanching times for drying.
See also: Blanching times for drying fruit
Blanching times for drying vegetables
This table is just meant as a handy summary for quick time reference. Sources used are from 2012 onwards.
For actual detailed drying directions, please see a reputable source such as one of the books mentioned below and refer to the item in question that you are drying.
Where recommendations differ, we present the differing recommendations for you to decide.
BBB: Ball Blue Book. Muncie, Indiana: Healthmark LLC / Jarden Home Brands. Edition 37. 2014. Vegetable drying blanching tables on pages 166 to 167.
BAN: Butcher, Meredith L., Ed. The All New Ball Book of Canning and Preserving. New York: Oxmoor House. 2016. Vegetable drying blanching tables on pages 338 to 340.
PIN: Excalibur. Preserve It Naturally. Sacramento, California. 4th edition, 2012. Vegetable drying blanching tables on pages 26 to 27.
SETP: So Easy to Preserve. Elizabeth L. Andress and Judy A. Harrison. University of Georgia Cooperative Extension. Bulletin 989. Sixth Edition. 2014. Vegetable drying blanching tables on pages 349 to 351.
- All procedures assume thorough washing first;
- Steam blanching times start as soon as the lid is replaced on the pot of boiling water.
- Blanching times must be adjusted for altitude.
Blanching times table for drying vegetables
|Artichoke hearts||6 to 8||SETP||Per 175 ml (3/4 cup / 6 oz) blanching water, add 1 tablespoon lemon juice|
|Aspargus||3 1/2 to 4 1/2||4 to 5||SETP, BBB||Cut thick stalks in half.|
|Beans -- Green or wax||2||2 1/2||SETP||Freeze 30 to 40 minutes after blanching for better texture when dried.|
|Beans -- Lima||2 to 3||3 to 5||PIN|
|Beets||Cook fully||SETP, BBB|
|Broccoli||2||3 to 3 1/2||SETP||Quarter stalks|
|Brussels Sprouts||4 1/2 to 5 1/2||6 to 7||SETP||Cut in half|
|Cabbage||1 1/2 to 2||2 1/2 to 3||SETP||Shred into thin strips|
|Carrots||3 1/2||3 to 3 1/2||SETP, BBB||Thin slices or strips|
|Cauliflower||3 to 4||4 to 5||SETP|
|Corn||BBB, PIN||BBB and EXCAL say steam cook cobs until milk is set, then scrape off kernels.|
|Cucumber||0||0||PIN||No blanching needed.|
|Garlic||0||0||SETP||No blanching needed.|
|Greens (chard, kale, turnip tops, spinach)||1 1/2||2 1/2||SETP|
|Horseradish||0||0||SETP||No blanching needed.|
|Kohlrabi||3 to 5||5 to 8||PIN|
|Leeks||0||0||BBB||No blanching needed.|
|Lettuce||0||0||PIN||No blanching needed but may steam blanch until wilted|
|Mushrooms||0||0||SETP, BBB||No blanching needed.|
|Okra||0||0||SETP, BBB||No blanching needed.|
|Onions||0||0||SETP, BBB||No blanching needed.|
|Parsley||0||0||SETP||No blanching needed.|
|Peas (black-eyed)||0||0||PIN||No blanching needed.|
|Peas (green garden peas)||2||3||SETP, BBB|
|Peppers including pimientos and hot peppers||0||0||SETP, BBB||No blanching needed.|
|Popcorn||0||0||BBB||No blanching needed. Leave kernels on cobs until dried.|
|Potatoes (white)||5 to 6||6 to 8||SETP, BBB||SETP says steam 6 to 8, BBB says 5 to 6.|
|Pumpkin||1||2 1/2 to 3||SETP|
|Radishes||0||0||PIN||No blanching needed.|
|Rutabaga||3 to 5||BBB|
|Squash -- Summer||1/2||2 1/2 to 3||SETP|
|Squash -- Winter||1||2 1/2 to 3||SETP, BBB||BBB gives steam option only.|
|Tomatoes for stewing||1||3||SETP||Peel first. Cut into 3/4 inch thick wedges or slices.|
|Tomato slices||0||0||SETP||No blanching needed.|
|Turnip||3 to 5||BBB|
|Zucchini||1/2||2 1/2 to 3||SETP|
Beans, Green or wax: Ball Blue Book says steam blanch for 4 to 6 minutes, then freeze 30 minutes (SETP also recommends the freezing step.) Ball All New drops freezing step.
Celery: Ball All New says steam blanch 4 to 6 minutes.
Mushrooms: PIN says you can optionally steam blanch for 2 to 3 minutes.
Okra: PIN says water blanch 2 to 3 minutes, or steam blanch 4 to 5 minutes
Tomatoes: Ball Blue Book advises to peel first regardless of intended use. PIN implies the same. Ball All New says peel if desired.
Zucchini: Ball Blue Book advises to dry without blanching. PIN advises not to steam blanch if you are intending the slices to be snacking chips.
Kendall, Patricia. High Altitude Food Preparation. Colorado State University Extension. 2013. Page 3. http://extension.colostate.edu/topic-areas/nutrition-food-safety-health/high-altitude-food-preparation-p41/ ↩