Green Cabbage in 6% brine
14.0 days at 68 °F · pH target 3.40 · outside typical range
Brine calculator
For submerged vegetables (cucumbers, peppers, cauliflower, garlic scapes). Salt mass is expressed as a percentage of water mass — NCHFP convention.
1 L of water ≈ 1 kg. 3.5% brine = 35 g salt per litre.
About Green Cabbage
The canonical lacto-ferment vegetable. Green cabbage is the backbone of traditional sauerkraut across German, Polish, and Russian cuisine. High water content (~92%) means it self-brines when salted and weighted — no added water required. Produces abundant Lactobacillus after 3-5 days at room temperature.
Fermentation data
- Default salt
- 2%(you are viewing 6%)
- Salt range
- 1.5–3%
- Time at 68°F
- 14.0 days
- pH target
- 3.40
- Water content
- 92%
- Preferred styles
- sauerkraut, kimchi baechu, curtido
Note: 6% is outside the typical brine range for Green Cabbage (1.5–3%). The recommended default is 2%. View 2% brine + Green Cabbage.
Technique
Shred fine (2-3mm) across the grain. Weigh, salt at 2% of vegetable weight, massage 8-10 minutes until liquid pools. Pack into a weighted crock or jar below brine. Keep 65-72°F for 2-4 weeks depending on taste preference. Taste weekly from day 7.
Brine notes at 6%
60g salt per 1L water. Almost too salty to eat directly — the finished product (fish sauce, garum) is used as a seasoning, not consumed neat. For vegetable ferments, only use in tropical-climate long ferments where 5% is inadequate. Noma Guide: 6% used for some of their rapid-ferment glass-jar garums.
What a 6% brine does for Green Cabbage
A 6% brine is 60 g of salt in every litre of water. That salt pulls moisture out of the cabbage by osmosis and, more importantly, tilts the jar in favour of salt-tolerant Lactobacillusover the spoilage microbes that can't handle it. A stronger brine ferments more slowly, keeps the vegetable firmer and crunchier, and stores longer; a weaker one ferments faster and softer.
Safety: Preserving brine. Fermentation will be very slow; flavour strongly salty. Used for long-keeper pickles, olive cures and fish-sauce bases. Target pH once soured: ~3.40 (below pH 4.6 is the fermented-vegetable safety threshold).
Brine recipe for a 1-litre jar
| Water | 1 L (1000 g) |
| Salt (6%) | 60 g |
| Green Cabbage, packed | ~650 g |
Dissolve the salt fully, cool the brine to room temperature, pack the cabbage, and pour over until submerged. Use the calculator above to scale to your exact jar or crock.
How long Green Cabbage takes at your kitchen temperature
Green Cabbage takes about 14 days in a 6% brine at the 68°F baseline. Fermentation speeds up as the room warms and slows as it cools — the days below are that baseline scaled by temperature:
| Kitchen temp | Approx. days | What to expect |
|---|---|---|
| 55°F (12.8°C) | 37.6 d | slow, clean |
| 60°F (15.6°C) | 26.9 d | classic range |
| 64°F (17.8°C) | 19.6 d | classic range |
| 68°F (20°C) | 14 d | baseline |
| 72°F (22.2°C) | 11.2 d | fast — check daily |
| 76°F (24.4°C) | 8.8 d | fast — check daily |
Temperature multipliers after the Noma Guide to Fermentation (pp. 53–57) and Katz, The Art of Fermentation (ch. 3). Below ~50°F ferments effectively stall; above ~82°F, mould and kahm yeast rise fast — taste and refrigerate early.
Green Cabbage in 6% brine — FAQ
How much salt do I need for a 6% brine?
Dissolve 60 g of non-iodised salt (fine sea or pickling salt) in every 1 litre (1000 g) of water — that is 6% by weight. For a partial jar, scale it with the calculator above; the ratio stays the same.
How long does Green Cabbage take in a 6% brine?
About 14 days at the 68°F baseline. It runs slower in a cool room (~26.9 days at 60°F) and faster when it's warm (~9.4 days at 75°F). Start tasting from day 7 and refrigerate once it's as sour as you like.
Is a 6% brine strong enough and safe?
Preserving brine. Fermentation will be very slow; flavour strongly salty. Used for long-keeper pickles, olive cures and fish-sauce bases. As it ferments, cabbage should drop to about pH 3.40 — comfortably under pH 4.6, the acidity threshold the NCHFP and FDA treat as safe for fermented vegetables.
Why keep the cabbage under the brine?
Under the liquid the environment is oxygen-free, which is exactly what the Lactobacillus you want thrives in and what surface moulds and kahm yeast cannot tolerate. Anything poking above the brine is at risk — weigh the vegetables down so everything stays submerged.
Is cloudy brine or a white film normal?
Cloudy brine and a little sediment are normal signs of an active lacto-ferment. A thin, flat white film on the surface is usually kahm yeast — harmless; skim it off. Only fuzzy, raised, or blue/green/black growth is mould, in which case discard the batch.
Explore other brine concentrations for Green Cabbage
- 2.5% — lightly-salted vegetable brine
- 3% — standard half-sour brine
- 3.5% — NY deli half-sour
- 5% — full-sour / long-ferment brine
- 6% — fish sauce / garum base (current)
Sources
- NCHFP (UGA) — Fermented Sauerkraut
- NCHFP (UGA) — Fermented and Pickled Products
- Linda Ziedrich, The Joy of Pickling (3rd ed., 2016)
For educational use only. Consult your local food safety authority for commercial production.
The kit for fermenting Green Cabbage
A short, honest kit for lacto-fermentation. The scale is the one that matters most — everything here is by weight.
- Digital kitchen scale (0.1 g)Salt % is by weight, not volume — a 0.1 g scale is what makes the math above accurate.View on Amazon →
- Glass fermentation weightsKeep vegetables submerged under the brine line so they ferment safely without mould.View on Amazon →
- Airlock fermentation lidsLet CO₂ escape while keeping oxygen out — wide-mouth lids that fit standard jars.View on Amazon →
- Wide-mouth mason jarsThe workhorse vessel for kraut, kimchi and brine pickles — 1 qt and ½ gal sizes.View on Amazon →
- Pickling / fine sea saltPure salt with no iodine or anti-caking agents, which can cloud brine and inhibit fermentation.View on Amazon →
- Stoneware fermentation crockFor scaling past the jar — a water-sealed crock for 5 L+ batches with built-in weights.View on Amazon →
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