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Getting to Know: Fermented Foods

You might be surprised to learn that familiar items like bread, coffee, beer, and chocolate wouldn’t exist without fermentation. This ancient, natural process—which relies on the transformative powers of friendly bacteria—not only helps preserve food but also alters its textures, flavors, and aromas.

You might be surprised to learn that familiar items like bread, coffee, beer, and chocolate wouldn’t exist without fermentation. This ancient, natural process—which relies on the transformative powers of friendly bacteria—not only helps preserve food but also alters its textures, flavors, and aromas.

Miso

Miso: Miso is made by mashing cooked soybeans with salt; grains like rice, barley, or rye; flavorings; and koji, which is rice that has grown a healthy mold that produces a sweet, delicate fragrance. In the United States, you’re most likely to find the mild, sweet white shiromiso; intense red aka; and pungent, dark-colored hatcho. We like the first two to deepen the flavor of salad dressings, glazes, and marinades.

Sauerkraut

Sauerkraut: True sauerkraut is the result of wild fermentation (meaning that it uses lactic acid bacteria already present in and on the vegetable). It is often flavored with either juniper berries or caraway seeds. It’s bacteria, though, that lends sauerkraut its trademark flavor. Sauerkraut can be served piled on a Reuben sandwich or used as an ingredient in cooked dishes like our Kielbasa Casserole (see related content).

Fish Sauce

Fish Sauce: Fish sauce is called nuoc nam in Vietnam and nam pla in Thailand, but its pungent, fishy aroma is unmistakable. Made from salted, fermented fish, water, salt, and sometimes sugar, it’s a highly concentrated liquid that adds complexity to foods—and when used carefully, no trace of fishiness. And it’s not just for Asian dishes: We use it for depth in our Gumbo (see related content). Find it in most supermarkets near the soy sauce.

Yogurt

Yogurt: This fermented milk product comes from the Turkish word for “condense.” Milk is heated and then cooled to just over 100 degrees before a bacteria culture is added. After 4 to 8 hours, the mixture thickens into yogurt. You can use yogurt in sauces, in salad dressings, or as a topping as you would sour cream. Yogurt adds moisture and tangy flavor to our Lemon–Poppy Seed Muffins (see related content).

Kimchi

Kimchi: While this spicy, crunchy Korean pickle is most commonly made with napa cabbage, it can be made with radish, cucumber—even watermelon rind. The vegetables are chopped and then salted (to pull out moisture) or packed in a liquid brine. Since the vegetables release carbon dioxide as they ferment, kimchi often has an effervescent quality; some versions have chiles for heat.

Sour Pickles

Sour Pickles: Unlike sweet pickles, which are preserved in a vinegar solution, true sour pickles (and half-sours, which use less salt) are the product of fermentation. Herbs and spices like dill, mustard seed, coriander, or garlic add dimension. After as little as a week in solution, the lactic acid bacteria have done their work and the pickles are salty, sour, and crisp.

Chocolate

Chocolate: Without fermentation, products made from the cacao plant would taste acrid. After the cacao pods are picked, the beans and pulp inside are scooped out and left to sit outdoors for four to seven days, often in wooden crates. Naturally occurring yeasts grow on the pulp, helping decrease the overall pH level. The pulp is discarded and the beans are dried in the sun before being refined into cocoa.

Kefir

Kefir: Kefir, which is becoming more widely available in supermarkets, is akin to a drinkable yogurt. Kefir cultures are added to milk and left to ferment at room temperature for as little as 24 hours and then refrigerated for a few days. As the milk ferments, it becomes thicker and takes on a tart, sometimes bubbly quality. You can drink kefir straight or blend it with fruits or vegetables for a smoothie.

Soy Sauce

Soy Sauce: Made from soybeans and wheat, salty, pungent soy sauce is left to ferment anywhere from two days to four years, which can explain the widely divergent flavors and quality of different commercial brands. We take advantage of its flavor-boosting qualities to intensify beef stew, meatloaf, and even pot pies. Our favorite is Lee Kum Kee Table Top Premium Soy Sauce.

Preserved Lemons

Preserved Lemons: This savory take on citrus has Middle Eastern origins. Lemons are scored deeply, packed with coarse salt and lemon juice, and left to ferment for six to eight weeks. As the lemons ferment, the rinds soften in texture and mellow in flavor. Once preserved, the rinds (as well as the flesh, if desired) can be chopped to add a tart, salty-sweet note to braises, pan sauces, vinaigrettes, and more.

Vinegar

Vinegar: Vinegar is the last stop on grape juice’s fermentation adventure. Its initial fermentation turns it into wine, of course, but if left undrunk and exposed to air and room temperature, over time bacteria and yeasts in the wine convert the sugars into acid. To speed things up, manufacturers often use a vinegar “mother,” a thick blob of cellulose and acetic acid–forming bacteria.

Salami

Salami: Salting and drying is essential for any cured meat, but salami recipes also typically include a starter culture of lactic acid–producing bacteria that acts as a preservative and lends a signature, faintly sour flavor. The lactic acid feeds on carbohydrates in the mix (often sugar) while the salted meat rests, ferments, and dries in cool storage over several months.

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