Fermentation

Many food, drink, and industrial processes use micro-organisms. Micro-organisms can be introduced into a substance on which they are able to feed. The micro-organisms use the food source to obtain energy and in this process change some substances into others. These new substances may be useful to us. This process, fermentation, is often carried out in a vessel called a fermenter.
Fermenters require specific conditions, which include excluding other micro-organisms (aseptic precautions), monitoring nutrient supply, providing the optimum temperature and acidity (pH), oxygenation, and agitation (mechanical mixing).