How to Ferment Vegetables

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Lacto-fermentation provides the only effective way to pickle most vegetables. The vinegar method that works for cucumbers doesn't work as well on fibrous, dense vegetables. Instead of vinegar, lacto-fermentation employs salt to kill harmful bacteria and create an environment that lactobacillus, a beneficial bacteria that preserves and sours, can thrive in. You use the same fermentation method for all vegetables, so you have thousands of different mixes, melanges and medleys you can create.

Selecting the Vegetables

You can ferment any vegetable. But you get best results when you let the seasons dictate which group of vegetables to ferment and letting your tastes determine which vegetables in the group to ferment in each batch. You can take a specific approach by choosing the same type of vegetable, such as roots. For example, a mix of turnips, beets, radishes and parsnips hits all the taste sensations roots provide. Or you can take a general approach by selecting vegetables according to the four seasons. In summer, for example, you can go with jalapenos, zucchini, garlic and tomatillos for a zesty mix that pairs well with summer foods.

Prepping the Vegetables

Rinse the vegetables under cool running water and trim off any stems. Slice the vegetables into uniform pieces. Slices 1/8 inch thick ferment in as little as a week, where as slices ½ inch thick can take a month. Pack the sliced vegetables into canning jars, leaving about 2 inches of headspace.

Adding Antimicrobial Spices

Microbes can adapt to acidic environments that foodborne bacteria and mold can't survive in. Antimicrobial spices do what acids can't: Prevent occurrences of acid-loving bacteria in fermented foods. Packages of pickling mix contain spices with varying degrees of antimicrobial properties while delivering a well-rounded flavor. You can make your pickling mix using as many antimicrobial spices as you like. Bay leaves, cloves, mustard seeds, sage, thyme, rosemary, celery seeds, allspice, cinnamon and black pepper all have antimicrobial abilities. Add 1 to 2 tablespoons of pickling spices per quart-sized jar of pickled vegetables.

Starting Fermentation

Mix 3 tablespoons of kosher or sea salt per quart of filtered or spring water until dissolved. Pour the saltwater over the vegetables and spices in the jars until you fill them 1 inch from the top. Seal the jars with their lids and place them in a cool, dark cupboard or closet.

Determining Fermentation Time

Fermenting time varies with the density, starch and sugar content of the vegetables. Even the air temperature affects fermentation time; the warmer it is, the faster the vegetables ferment. However, it ultimately depends on your taste and how tart you want the vegetables. To determine exact fermentation time, you have to use the best tool for the job: your palate. Check the vegetables every 24 hours and open the jars to release the built-up carbon dioxide once a day. Start tasting the vegetables after 3 days to determine how long they need. When they reach the desired tartness, transfer the jars to the refrigerator and store up to 1 month.