Fermentation is a metabolic process that consumes sugar in the absence of oxygen. The products are organic acids, gases, or alcohol. It occurs in yeast and bacteria , and also in oxygen-starved muscle cells, as in the case of lactic acid fermentation . The science of fermentation is known as zymology . In microorganisms, fermentation is the primary means of producing ATP by the degradation of organic nutrients anaerobically . Humans have used fermentation to produce drinks and beverages since the Neolithic age . For example, fermentation is used for preservation in a process that produces lactic acid as found in such sour foods as pickled cucumbers , kimchi and yogurt (see fermentation in food processing ), as well as for producing alcoholic beverages such as wine (see fermentation in winemaking ) and beer . Fermentation occurs within the gastrointestinal tracts of all animals, including humans Fermentation turns NADH and pyruvate produced in glycolysis
An agrochemical or agrichemical , a contraction of agricultural chemical , is a chemical product used in agriculture . In most cases, agrichemical refers to pesticides including insecticides , herbicides , fungicides and nematicides . It may also include synthetic fertilizers , hormones and other chemical growth agents , and concentrated stores of raw animal manure . Many agrichemicals are toxic, and agrichemicals in bulk storage may pose significant environmental and/or health risks, particularly in the event of accidental spills. In many countries, use of agrichemicals is highly regulated. Government-issued permits for purchase and use of approved agrichemicals may be required. Significant penalties can result from misuse, including improper storage resulting in spillage. On farms, proper storage facilities and labeling, emergency clean-up equipment and procedures, and safety equipment and procedures for handling, application and disposal are often subject to m