Fermentation is an essential metabolic phenomenon that basically takes place in absence of oxygen
(O2). In the process of fermentation, sugar is consumed in the absence of oxygen. The products
formed due to fermentation are organic acids, gases, or alcohol. Fermentation occurs commonly
in yeast and bacteria and also in oxygen-starved muscle cells, as in the case of lactic acid fermentation.
In terms of microbiologists, fermentation is a primary means of producing ATP by the degradation of
organic nutrients anaerobically, in presence of suitable microorganisms. Zymology is the science of
fermentation. Fermentation processes are believed to have been developed in order to preserve fruits
and vegetables for times of scarcity by preserving the food by organic acid and alcohols, impart
desirable flavour, texture to foods, reduce toxicity and decrease cooking time. Fermentation is a
desirable process and the products that are being prepared by natural fermentation are fermented
products. That includes pickles, sauerkraut, yogurt, kimchi, cheese, etc