Malolactic Fermentation

A secondary bacterial conversion (not true fermentation) where Oenococcus oeni bacteria convert sharp malic acid into softer lactic acid. This reduces acidity, adds body, and creates buttery, creamy flavors (diacetyl). Standard for most reds and oaked Chardonnay, but deliberately avoided in wines where crisp acidity is desired (Riesling, Sauvignon Blanc).