ABSTRACT
Lactic acid bacteria are generally gram-positive, immobile, non spore forming, anaerobic, and even air-tolerant to some extent. They can ferment sugars, thus producing lactic acid alone (homofermentative bacteria), or a mixture of lactic acid, acetic acid, C 02 and ethanol (heterofermentative bacteria). They have high requirements for nutrients, such as amino acids, peptides, vitamins, fatty acids and some minerals. The plant environment is not generally suitable for their development. Nutrients that are crucial for their growth are rendered from the plant medium through salting or the addition of certain ingredients (whey, bran, etc.). The simultaneous growth of prototrophic bacteria supplies the lactic acid bacteria with metabolites which are essential for their multiplication.
