Making your own lacto-fermented pickled red onions is a super easy process. All you need are a few basic ingredients: onions, salt, pickling spices and a culture starter.
Compared to other fermented food recipes, this one doesn't involve special food-specific cultures but can be made with any probiotic supplement powder. Some we like to use include: Jarrow Formulas Jaro-Dolphilus, Body Ecology Culture Starter or PuraDyme LiyfBiotic probiotic powder. (See our Shop Related Products section below.)
Honestly, the hardest part about making pickled red onions is chopping the onions themselves. But only a few tears later you will have a packed jar ready for your salty brine blend. As an alternative to hand chopping, if making a large quantity, you can also use a food processor with the slicing blade attachment.
Red onions are our personal favorite of the Allium vegetables for their vibrant magenta pigmentation that’s high in anthocyanin content. After fermenting them for about a week they will develop a nice soft sweet pickled taste that also takes on whatever spice flavorings you incorporate into the recipe.
In this one, we use a pickling spice purchased from Mountain Rose Herbs, but you can also mix up any combination of spices you may have in your pantry or spice rack. We have used dill seeds, caraway, black seeds, mustard seed, fennel, ginger root and cumin seeds.
One thing we always include in our homemade pickled red onions these days is red beet juice powder. We tried it a few years ago and noticed it provides a sweeter taste as well as turns them a fun pink color, which incidentally looks great on salads or meals if you’re into food stylizing.
Pickled red onions also make a nice alternative to sliced onions in their raw state, which can sometimes be harder to digest for some people.
When lacto-fermenting onions we don't use vinegar or sugar, but rather ferment them in a salt-water brine like we would any cultured vegetable. (Examples of which include our kimchi, sauerkraut, green beans and grape leaves.)
When packed tightly in a jar or vessel under the liquid brine in an oxygen-free environment, the beneficial strains of lactic acid bacteria or LAB's can proliferate. This is most ideally achieved at a room temperature of 68-72°F (20-22°C).
This age-old technique eliminates pathogenic varieties and acts as a natural food preservative. Lactic acid bacteria are either rod-shaped (bacillus) or spherical (coccus) and are distinctly characterized by their tolerance for acidic environments with a lower pH. This gives them the upper hand against other strains of not so friendly bacteria that can't withstand high lactic acid concentrations.
The best part about lacto-fermentation is you are creating a LAB-friendly food, is this case probiotic-infused onion slices!
You can make this recipe in small or larger batches, depending on how often you use them up. Here are two recipe conversions for a half quart jar and a one quart jar.
It is important when making fermented foods to thoroughly wash all utensils, jars and chopping boards to avoid potential contamination. From our experience, fermented onions rarely seem to grow any surface molds, but you can use an air lock cap if you'd like to help keep out air-borne species.
We do always use glass crock rocks ("fermentation weights") on top to ensure they are fully submerged in the brine solution.
We store our pickled red onions with brine in a sealed jar in a cool pantry location or they can be stored in the fridge.
Enjoy them as a sweet and savory accent atop meals or on salads.