Term for the transformation of malic acid into the milder tasting lactic acid (lat. malum = apple, lac = milk), which plays an alternative role in the production of fruit juice, wine and sparkling wine(champagne, sparkling wine). The process is also known as biological acid degradation (BSA), bacterial malic acid degradation, microbial acid degradation or apple-lactic acid fermentation, as carbon dioxide is also released. However, this is not actually a real fermentation, but was previously thought to be one. Around 1890, Dr. Hermann Müller-Thurgau (1850-1927), who was working in Geisenheim at the time, correctly assumed that bacteria were the cause. Dr. Wenzel Seifert (1862-1942) was then able to identify the acid-degrading bacterium at the Klosterneuburg Viticulture Institute in 1903 and named it "Micrococcus malolacticus". Today, the BSA is almost always used for red wine, but always before a barrique ageing. The advantages are reduction of malic acid, more fullness due to the lactic acid, lower sulphur dioxide requirement and better microbiological stability.