Fermented Red Onions

If you shy away from onions because of their strong flavor, try fermenting them. As Kristi explains in this post, the fermentation process creates an onion with a more delicate flavor.

Fermented red onions are crunchy and packed with flavor. While raw onions can be overpowering to a dish, fermented onions offer a more delicate, subdued flavor. With the beautiful purple color of the red onions still shining through, they add not just a vibrant flavor to a dish, but also a vibrant color.

Onions offer a variety of benefits when raw. Fermenting onions sometimes increase these wonderful benefits. Fermented onions offer higher antioxidant levels for instance.

How to Make Fermented Onions


• A set of Fermentools  or just a starter kit , or you can use a different fermentation vessel.
• Wooden spoon for stirring.
• Toothpicks for taste testing. Using a metal fork may interfere with the fermenting process.
• Mason jar or other vessel


• 3 large onions, or enough to fill your fermenting vessel.
• 5% brine using Himalayan Salt
• Filtered Water


Fermenting red onions is a pretty simple process. Just follow the directions here.

1. Slice onion thin.
2. Add onions to the fermenting vessel leaving a 1 inch head space.
3. Place weights on top of the onions.
4. Pour in just enough brine  to cover the onions.
5. Secure Fermentools onto jar or prepare other vessel similarly.
6. Store in a place away from sunlight, with a temperature around 65°F to 75°F.
7. Ferment for five days, and place in the refrigerator when completed.

Fermented red onions are beautiful tossed in a green leaf salad. Or, use them as a substitute in a recipe calling for raw red onions. They also make a beautiful garnish, as they maintain their beautiful purple hues even through the fermenting process. Place them decoratively around the plate or bowl. They will make the dish look elegant and people will enjoy eating them.


Most failed ferments are caused by air. To keep your vegetables from coming in contact with the air, make sure they are submerged below the brine with a glass weight. Fermentools’ glass weights are cut the perfect size to fit in the top of a wide-mouth Mason jar. You can buy them singly, or as part of a kit.


Kristi is the blog owner of HomesteadWishing.com She is a wife and mother of three wonderful boys. She loves to write about food, children & parenting, tips and tricks, and survival information.

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