Editing Malolactic fermentation (section)

===Tourne===
Compared to malic and citric acids, tartaric acid is usually considered microbiologically stable. However, some species of ''Lactobacillus'' (particularly ''L. brevis'' and ''L. plantarum'') have the potential to degrade tartaric acid in wine, reducing a wine's total acidity by 3-50%. French winemakers had long observed this phenomenon and called it ''tourne'' (meaning "turn to brown")<ref name="Wine Faults"/> in reference to the color change that can occur in the wine at the same time likely due to other processes at work in addition to the tartaric loss. While ''Lactobacillus'' is the most common culprit of ''tourne'', some species of the spoilage film yeast ''[[Candida (fungus)|Candida]]'' can also metabolize tartaric acid.<ref name="Wine Micro"/>