Fermentation is a process in which food is exposed to bacteria and yeasts, or naturally through the air. Beneficial microorganisms beat out the kind that can kill you, and eat up the carbohydrates in the food. The results are interesting flavors, textures, and smells. Before refrigeration, curing meats, pickling vegetables, and clabbering milk was the only way to extend the life of perishables. And if fermented foods haven’t been cooked, they are really good for you