Lactic acid fermentation

Lactic acid fermentation is the process in which microorganisms break down sugars to produce lactic acid. There are two main types: homolactic and heterolactic. In homolactic fermentation, almost all of the glucose (C6H12O6) is converted into two molecules of lactic acid (C3H6O3). In heterolactic fermentation, the glucose yields not only lactic acid but also ethyl alcohol (C2H5OH) and carbon dioxide (CO2). In sake brewing, lactic acid fermentation plays an important role, contributing to a richer aroma and flavor. The lactic acid produced through this process adjusts the sake's acidity and also helps to inactivate unwanted microorganisms.