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Term (biological acid degradation) for the process following alcoholic fermentation or possibly already started during this process, especially in red wine production; see malolactic fermentation.

Term for the conversion of malic acid into the milder lactic acid (Latin 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, it is not a real fermentation, but was previously thought to be. Around 1890, Dr Hermann Müller-Thurgau (1850-1927), who was working in Geisenheim at the time, correctly suspected bacteria as the cause. Dr Wenzel Seifert (1862-1942) was able to identify the acid-degrading bacterium at the Klosterneuburg Viticulture Institute in 1903 and named it "Micrococcus malolacticus".

Malolaktische Gärung - Zeichnung

Start of the process

This natural process can take 10 to 40 days. It is initiated spontaneously from around 16 °Celsius by existing or added bacteria (Oenococcus oeni). However, the process can also be started by stirring lees, by blending with a wine already in the BSA process or (usually the...

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