From harvest to shelf, we teach you how to use lacto-fermentation to preserve food
As the summer crawls steadily onward, gardeners are increasingly overwhelmed by their bounty. Vegetables ripen at what seems like lightning speed. Zucchini appear overnight, green beans hang heavy on the vine. What’s a person to do to preserve all that goodness?
Well, ferment it, of course! With lacto-fermentation, we can store the harvest for months to come. Heads of Napa cabbage and carrots can become kimchi. Green beans ferment nicely into a snappy snack. Cucumbers can miraculously morph to become kosher dills.
But, knowing the basics of how your food is transformed into a shelf-stable, preserved form is essential. Once you’ve learned those, you’ll have garden produce at hand year-round.
Lacto-Fermentation: What You’ll Need
Two components make fermentation happen. First is naturally occurring lactic-acid bacteria, or LAB. These are used for culturing yogurt. They also convert sugars
to lactic acid, preserving food.
But they can’t do it alone. The other necessary ingredient is salt. Most harmful bacteria can’t survive in a salty environment. Salt’s also a natural preservative.
Using salt and lactobacilli, which exists in the air all around, your food practically preserves itself. Unfortunately, you can’t just pack your food in salt, because its juice would be drawn out.
Most people use water as a brine base, but be sure to use distilled water. This avoids any possible chemicals lurking in tap water that might kill your good bacteria.
You’ll need a container for this fermentation process to occur. Mason jars are a favorite, as they’re nonreactive and easy to sterilize. A sterile environment ensures your food is going to be safe to eat later. Another option is a jar with an airlock feature.
Getting the Fermentation Started
The process of lacto-fermentation isn’t a way to replace canning. It’s an entirely different process altogether. Fermented food will be edible for at least a couple of months beyond its normal shelf life. Refrigerator storage makes it last even longer.
But to do it, you first need produce. The fresher the produce is, the better it ferments. Root vegetables, like carrots or beets, are popular choices. These are natural carriers of lactobacilli from the soil. Other vegetables, such as green beans, cabbage, broccoli, cauliflower or cucumbers, are used as well. Peppers of multiple types are often fermented. You can even ferment some forms of fruit.
Begin by cleaning your vegetables. For green beans, you may want to parboil (partly cooking them by boiling) them first to lock in their green color. Others, like cucumber, can be rinsed off well to remove any dirt.
Next, make your brine. For most hard veggies, a good brine recipe combines 2 tablespoons kosher salt and 1 quart water. Softer vegetables or herbs may need up to 5 tablespoons of salt. When in doubt, err on the side of saltier brines.
Pack your vegetables tightly into the jars and completely submerge them in brine. Place a sterilized weight on top to keep your produce from floating if necessary. You can buy fermenting weights online, or make your own using mini jelly jars, condiment dishes or small dessert ramekins that you sterilize first.
How Long To Wait?
Now it’s a waiting game. First, the brine kills off bad bacteria. Then, the lactobacilli can get to work, creating pressure in the jar.
If you used an airlock on your jar, it will naturally release pressure. If you used a Mason jar, you’ll need to manually “burp” your jar twice per day to release any gasses formed by fermentation. To do this, you can either loosen the lid or slightly release it. Doing this regularly prevents exploding jars.
Most fermentation takes at least between eight to 10 days from the first sign that it’s working. You’ll be able to tell from small bubbles forming in the liquid. Keep your jar in a cool, dark location as it does its thing, and check it regularly.
After eight to 10 days, the food should be fermented.
Longer processing allows it to sour even more, increase its nutritional value and give an added boost of healthful probiotics. If you want a super-sour pickle, ferment for up to a month.
You can taste your food’s flavor as it develops, but make sure your hands are clean and you keep everything under the brine.
When you’re ready to stop the fermentation, pull off your airlock. Put on a regular Mason jar lid, and tuck it into the fridge. The cold will stop the fermentation process.
If that seems almost too easy, it’s because it is. This process has been used for centuries, and provides delicious, healthy produce long after the harvest ends.
Our editors picked out their favorite fermentation necessities and accessories to help you begin your own jarring journey. Find our recommendations for starter kits, salts, airlock seals, how-to books, containers and more.