What is Fermentation?

Think of some of your favorite foods. Yogurt, bread, sauerkraut, pickles. Drinks? Beer, cider, kombucha. What do they have in common?

They’re fermented.

Fermentation not only makes food nutritious and tasty, it’s also an ancient form of food preservation, born from time-honored rituals that were practiced long before anyone could grasp microbiology. There is evidence that the ancient Babylonians, as well as the Egyptians and other ancient civilizations around the world practiced fermentation of some kind.

Put simply, fermentation is the conversion from sugar to alcohol that is done by microbial life, such as yeast or bacteria. These microorganisms find an abundance of carbohydrates, which they eat and then excrete ethanol.

Sauerkraut and other vegetables in the process of fermenation.

Fermentation as a food-preparation technique was a symbiotic exchange between yeast or bacterial life and humans who had to convert excess foods, such as milk or cabbage, into preserved products with a longer shelf-life, yogurt and kimchi, respectively, in this example. Humans prepare an environment that microorganisms thrive in and the microorganisms, through their metabolic processes, convert chemicals in the food into less-reactive ones, thus increasing spoilage time. Fermented food is often living food, with the live cultures contributing to more digestive flora in one’s intestines, which, in short, leads to better digestion. Pickled foods often maintain their crispness and texture, which make them a welcome addition to winter-time diets, as other canned foods often have to be cooked quite a bit, in order to kill microbial life present. Fermented foods have enjoyed an increased popularity, as of late, as drinks, such as kefir and kombucha have been highlighted for their healthful effects. Author Sandor Elix Katz, for example, wrote Wild Fermentation, a cookbook and treatise on the benefits of fermented foods.

Fermentation of food and beverages implies desired effects. However, ancient brewers, such as monks, relied on wild yeast to ferment their wort (the non-alcoholic grain-tea mix that one ferments into beer). A careless brewer can expose their wort to undesired microbial life which will spoil their beer, giving it strange off-flavors which are quite often sour. Any other fermented food carries the risk of contamination, so being careful to maintain sanitary conditions and learn when a fermented food is discolored or smells different than it should is crucial. This shouldn’t scare you off from fermenting at home, however. As with any art, you may turn out a moldy batch of sauerkraut or some wine with “stuck” (halted and incomplete), fermentation. You’re only risking the ingredients. The reward you’ll receive is delicious, incredibly nutritious “living” food, the diversity of which is breath-taking. -MIKE KLEPFER

Further Reading:

Wild Fermentation, by Sandor Elix Katz

The Complete Joy of Homebrewing, by Charlie Papazian

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