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Lacto-Fermented Red Onions

Delicious Lacto-Fermented Red Onions recipe

Recipe Details

  • Yield: ** 1 Quart Jar
  • Prep time: ** ~15 mins
  • Texture target: TBD
  • Cook time: ** 0 mins (Fermentation: 5-7 days)

Ingredients

For 1 quart jar: - [ ] 1–2 red onions, peeled and sliced into rings or half-moons - [ ] 1 garlic clove (optional, adds depth) - [ ] 1/2 tsp black peppercorns (optional) - [ ] 1 bay leaf (optional) - [ ] 1 tsp coriander seeds or mustard seeds (optional) - [ ] 1 black tea bag (for crunch if you like — optional for onions)

Brine: - [ ] 2 cups water (dechlorinated) - [ ] 1 tbsp kosher salt (slightly less salty than the cucumbers — ~2% solution is better for onions)

You can also reuse the leftover brine if it’s fresh and not slimy — just top off with more water and salt if needed.

Method

  1. Slice onions and pack into the jar with any desired spices.
  2. Add brine until onions are submerged.
  3. Weigh them down — they float more than cucumbers! A fermentation weight or brine-filled zip-top bag works.
  4. Seal with your airlock lid.
  5. Ferment at room temperature for 5–7 days. Taste daily after day 3.
  6. Once tangy and translucent, move to the fridge. They’ll last months and keep getting better.

Flavor Tips:

  • Add a few slices of jalapeño or chili for spicy pickled onions.
  • Add a pinch of sugar for a mild sweet-and-sour deli vibe.
  • You can skip tannins (tea/grape leaf) for onions — they don’t need crunch like cukes do.

Calculating Brine Percentage

To make brine for any amount of water, use a scale: Water Weight (g) x Percentage = Salt Weight (g)

Example for 2% brine (recommended for onions): - 1,000g water x 0.020 = 20g salt - 500g water x 0.020 = 10g salt

Tags: #fermentation