As we all know, malolactic fermentation (MLF) is the conversion of malic acid to lactic acid with the production of carbon dioxide. The use of this secondary fermentation in white wines and more commonly in red wines is, in general, for three important reasons: (1) reduction in the titratable acidity of the wine, (2) flavour modification and (3) microbiological stability. What we sometimes do not understand is why this fermentation slows and stops, often resulting in grief and anxiety. Along wi...