Lacto-fermenting yellow onion: 3.00% salt, 10.0days at 68 °F
Strong sulfur compounds mellow during fermentation. Results sweeter and milder than raw. Often fermented as half-moon slices or whole small pearl onions.
Salt calculator
Enter your vegetable weight and a salt percentage. We return the exact salt mass in grams, plus teaspoons for each common grain.
grams
%
Grain matters: one teaspoon of Diamond Crystal weighs half as much as one teaspoon of fine sea salt. Weigh in grams when you can.
All salt grains
Grain
Grams
Teaspoons
Tablespoons
Diamond Crystal kosher
30 g
10.56
3.52
Morton kosher
30 g
6.25
2.08
Fine sea salt
30 g
5.27
1.76
Pickling / canning
30 g
5.45
1.82
Default salt
3.00 %
Salt range
2.50% – 3.50%
Time @ 68 °F
10.0 days
Target pH
3.80
Water content
~89%
Preferred styles
brine pickle, escabeche component
Technique
Slice thin (3mm) or use whole pearl onions. Cover with 3% brine + 1 bay leaf + 1 tsp coriander seeds per pint. 10-14 days. For mixed ferments, add at 20% of primary vegetable weight.
3.00% by weight is the default for yellow onion (workable range 2.50%–3.50%). For 1000g yellow onion, that's 30.0g salt. Use non-iodised salt and weigh in grams — teaspoon equivalences vary by salt grain. Source: Cultures for Health — lacto onions.
How long to ferment yellow onion?
10.0 days at 68°F (20°C). Cooler kitchens (60-65°F) slow fermentation; warmer kitchens (75-80°F) roughly halve the time per 10°F increase. Start tasting from day 5; target pH 3.80 or below indicates complete primary fermentation.
What's the best technique for fermenting yellow onion?
Slice thin (3mm) or use whole pearl onions. Cover with 3% brine + 1 bay leaf + 1 tsp coriander seeds per pint. 10-14 days. For mixed ferments, add at 20% of primary vegetable weight.
What category is yellow onion for fermentation?
Yellow Onion is a allium vegetable. Strong sulfur compounds mellow during fermentation. Results sweeter and milder than raw. Often fermented as half-moon slices or whole small pearl onions. Preferred fermentation style: brine-pickle, escabeche-component.
The kit for fermenting Yellow Onion
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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