What is fermented food?
Fermented foods are those whose preparation involves the action of natural bacteria, yeasts, or molds that ferment carbohydrates into alcohol or organic acids. This action not only preserves food but also enhances its flavor and nutritional profile. Fermented foods run the gamut from yogurt to kefir, sauerkraut, kimchi, kombucha, miso, and tempeh. Each food gives unique tastes, textures, and health benefits.
Science of Fermentation
Fermentation is a biochemical anaerobic process where microorganisms, mainly sugars, are degraded. The major microorganisms participating in this process include bacteria, yeast, and molds. These microorganisms, during the fermentation process, generate a number of by-products that include lactic acid, acetic acid, and alcohol, which are responsible for flavor, texture, and aroma in foods.
Key Forms of Fermentation
Lactic Acid Fermentation: Lactic acid fermentation is thought to be one of the most common types of fermentation foods. The examples include yogurt, sauerkraut, and kimchi. The LAB changes lactose and other sugars into lactic acid, thus providing the sour flavor and also acting as a preservative agent.
Alcoholic Fermentation: A process in which sugars are converted into ethyl alcohol and carbon dioxide by yeast. The main uses of this type of fermentation are largely in the brewing of beers, wines, and in the manufacture of spirits.
Fermentation of acetic acid refers to ethanol conversion by bacteria into acetic acid, forming the major constituent of vinegar. The commonly fermented foods are pickles and some types of sauces.
