Fermented foods: Microbiology, biochemistry and biotechnology

Abstract : Fermentation is one of the most ancient forms of food preservation technologies in the world that uses microorganisms to convert perishable and sometimes inedible raw materials into safe, shelf-stable and palatable foods or beverages. It can be described as a biochemical change, which is induced by the anaerobic or partially anaerobic metabolism of carbohydrates by microorganisms with the production of acids that result in decrease in pH, or with the production of alcohols. During fermentation, due to the incomplete oxidation of organic molecules, different products such as aromatic compounds are produced. Alkaline fermentation is a special type of fermentation that causes an increase in pH of the food. In that case, microorganisms degrade principally food proteins, leading to the release of ammonia resulting in increase of pH.