Fermented Red Onion
Lacto-fermented red onion
Ingredients
- Salt30g≈ 1.75 × 1 tablespoon
- Red Onion500g≈ 3.25 × 1 cup chopped
Estimated Cost
- Salt (30g)$0.04
- Red Onion (500g)$1.42
Prices are estimates based on Kroger grocery store data, last updated March 2026. Actual prices may vary by location and retailer.
Instructions
- 1
Peel the red onions and slice thinly (about 1/8 inch thick).
- 2
Pack the onion slices tightly into a clean quart-sized jar, leaving about 1 inch of headspace.
- 3
In a separate bowl, dissolve the salt in 1 liter (about 4 cups) of filtered, non-chlorinated water to create a 3% brine.
- 4
Pour the brine over the onions until they are fully submerged. Use a fermentation weight or small clean glass to keep the onions below the brine.
- 5
Loosely cover the jar (a fermentation airlock or loosely-set lid works — do not seal tight or pressure will build) and set at room temperature (65-75°F), out of direct sunlight.
- 6
Ferment for 7-14 days. Taste after day 7 — they are done when they are pleasantly tangy and softened to your preference.
- 7
Once fermented to your liking, tighten the lid and transfer to the refrigerator. Keeps for several months.
Nutrition per serving
Based on 12 servings · USDA data
Nutrition calculated from USDA FoodData Central using ingredient quantities in grams.
Nutrition values are estimates based on USDA data and may vary.