Sauerkraut and Fermented Pickles

How it works

Fermented vegetables are preserved by lactic acid bacteria that live on the vegetables themselves. Given salt, no air, and the right temperature, they turn the vegetables’ sugars into lactic acid, which sours them and keeps spoilage organisms out ¹. Regular dill pickles and sauerkraut take about three weeks; refrigerator dills about a week ¹.

Salt is what steers it: it draws juice out of the vegetables to make the brine and favors the desirable bacteria over others. That’s why the USDA says not to cut the salt in fermented recipes, and not to use reduced-sodium salt substitutes in them ². Use canning or pickling salt; table salt is safe but its anticaking agents can cloud the brine, and flake salt varies too much in density to measure ².

Containers and weights

From USDA Guide 6 ²:

• Allow 1 gallon of container for every 5 pounds of fresh vegetables; a 5-gallon stone crock holds about 25 lb of cabbage or cucumbers.
• Food-grade plastic and glass work as well as stoneware. Never garbage bags or trash liners. Quart and half-gallon Mason jars work for kraut but tend to lose more to spoilage.
• Keep the vegetables 1 to 2 inches under brine. Use a plate just smaller than the opening, weighted with 2 or 3 sealed quart jars of water, or a heavy food-grade bag holding 3 quarts of water with 4-1/2 tablespoons of salt (so a leak won’t dilute the brine).
• Cover with a clean, heavy towel against insects and molds.
• Wash the crock, plate, and jars in hot soapy water and rinse with very hot water first.

Sauerkraut step by step

USDA’s recipe uses 25 lb of cabbage and 3/4 cup of canning salt for about 9 quarts ²:

1. Use firm, fresh heads, and start the kraut within 24 to 48 hours of harvest.
2. Work 5 lb at a time. Remove the outer leaves, rinse, quarter, core, and shred to about the thickness of a quarter.
3. Put the cabbage in the crock with 3 tablespoons of salt, mix with clean hands, and pack firmly until the salt draws out the juice.
4. Repeat until all the cabbage is in. Leave 4 to 5 inches between the cabbage and the rim.
5. If the juice doesn’t cover the cabbage, add boiled and cooled brine of 1-1/2 tablespoons of salt per quart of water.
6. Add the plate and weights and cover with a towel.

Temperature and time

• 70-75 °F: fully fermented in about 3 to 4 weeks.
• 60-65 °F: about 5 to 6 weeks.
• Below 60 °F: it may not ferment.
• Above 75 °F: it may go soft ².

With a brine bag on top, leave the crock alone until the bubbling stops. With jars as weights, check two or three times a week and skim off any scum ². In a Wisconsin house, a fall batch in a 65 °F back room is slow but reliable; a summer batch in a hot kitchen risks soft kraut.

Fermented dill pickles

Per gallon of container ²:

• 4 lb of 4-in. pickling cucumbers, with 1/16 in. cut off the blossom end and 1/4 in. of stem left on.
• 2 tbsp dill seed or 4 to 5 heads of fresh or dry dill.
• Brine of 1/2 cup salt, 1/4 cup 5% vinegar, and 8 cups water.
• Optional: 2 cloves garlic, 2 dried red peppers, 2 tsp mixed pickling spices.

Put half the dill and spices in the crock, add the cucumbers and the rest, pour on the brine, and weight them under it. Ferment at 70-75 °F for about 3 to 4 weeks; 55-65 °F is acceptable but takes 5 to 6 weeks; above 80 °F they go soft. Check several times a week and skim scum or mold promptly. If the pickles become soft, slimy, or smell bad, discard them ².

Keeping the batch

• Refrigerated: fully fermented kraut keeps several months tightly covered; fermented pickles about 4 to 6 months in the original container if scum is removed regularly ².
• Canned: kraut can be hot packed (brought slowly to a boil) or raw packed with 1/2-in. headspace and processed in a boiling-water canner, hot-packed pints 10 minutes and quarts 15 at 0-1,000 ft. For pickles, heat the brine to a boil, simmer 5 minutes, pack with 1/2-in. headspace, and process raw-packed pints 10 minutes and quarts 15 at 0-1,000 ft, or use low-temperature pasteurization ². Canning stops the fermentation and makes it shelf-stable, but softens the texture.

Try it

Make a half-gallon jar batch first: 5 lb of cabbage and 3 tablespoons of salt, packed into two half-gallon jars with a small brine-filled bag in each. Keep them at 65-70 °F and taste a forkful each week until it’s sour enough, then refrigerate.

What to take from this

Lactic acid bacteria sour vegetables under salt, without air, at the right temperature. Use 3 tablespoons of canning salt per 5 lb of cabbage, pack until juice covers it, keep it 1-2 in. under brine with a brine-filled bag, and ferment at 70-75 °F for 3-4 weeks (5-6 at 60-65 °F). Fermented dills use 1/2 cup salt, 1/4 cup vinegar, and 8 cups water per gallon. Skim scum; discard anything soft, slimy, or foul. Refrigerate or can the finished batch, and never cut the salt.