How to Make Lacto-Fermented Onions
Learn how to make lacto-fermented onions. Lacto-fermenting is a simple, traditional method that makes onions more digestible, boosts their nutritional value, and adds gut-healthy probiotics to your diet, all while preserving your harvest.
Equipment
- Cutting board and knife(s).
- Wide mouth mason jars (16-oz size).
- Fermentation weights or clean small jars to hold carrots under the brine.
- Fermentation lids or regular mason jar lids.
Ingredients
- 3 medium-size onions
- 1 liter filtered water
- 5 tsp (~30 grams) sea salt
- 1/2 tsp dry terragon or thyme optional
- 1/4 tsp crush black pepper optional
- 1/4 tsp mustard seed powder optional
Instructions
- Make a brine by dissolving 5 teaspoons of salt in 1 liter (about 4 cups) of filtered water. Warm up a portion of the water to help dissolve the salt, then add the remaining water. Stir well and let the brine cool to room temperature.
- Peel your onions and slice them into medium-thin rounds or half-moons, depending on your preference.
- Pack the sliced onions tightly into clean jars. Add any optional herbs or spices, then pour the brine over the onions until fully submerged.
- Use fermentation weights, a clean jelly jar, or a slice of onion to weigh the onions down and keep them completely submerged under the brine.
- Close the jars loosely with lids, or use fermentation lids. Place the jars on a dish or tray to catch any brine that may overflow during fermentation.
- Let the onions ferment at room temperature for about 1 to 2 weeks, depending on the temperature of your home. Burp the lids daily (if using regular lids) and check to ensure the onions stay submerged. Press down and add more brine if needed. Begin tasting after a few days to determine when the flavor and texture are just right for you.
- Once fermented to your liking, seal the jars tightly and move them to the refrigerator. The onions will keep for several months, becoming more mellow and complex over time.
Notes
You can use any kind of onions for fermenting, according to your personal preference. Use red onions for a bolder flavor, and beautiful color. Yellow and sweet onions have a milder and sweeter taste, while white onions have a sharper taste and stay more crunchy.
This fermented onions are delicious plain, but you can add your choice of favorite herbs and/or spices for an extra boost of flavor. Garlic, thyme, dill, peppercorn are some good options. You can also add a bit of sugar for extra sweetness and to boost the fermentation process.
These fermented onions should be stored in the refrigerator. In optimal conditions they last up to 6 months. Watch for any sign of mold or spoilage (off smell, taste, and texture).