In batch fermentation at 45 C and controlled pH of 65 strain E. However in some circumstances they can be responsible for food spoilage. Pin On Wardbiology Alcoholic and lactic acid. . Worldwide lactic acid production from microbial fermentation accounts for around 90 of the total lactic acid production Hofvendahl and Hahn-Hägerdal 2000 and has attracted interest because of its numerous advantages compared with chemical synthesis such as production of pure isomers and the use of renewable resources as fermentation substrates. Commercially this is typically achieved through metabolic pathways of Lactic Acid Bacteria LAB species but yeast and even humans are also capable of producing lactic acid. Lactic acids flavour-generating components eg acetaldehyde ethanol and carbon dioxide are all by-products of fermentation and contribute to the organoleptic properties of kefir. Pyruvate molecules from glucose glycolysis may be furt...