Wine Scholar Guild Champagne Master Practice Test

Malolactic fermentation is the process by which lactic acid bacteria convert malic acid (the sharper, green-apple acidity in wine) into lactic acid (softer and creamier in texture). This typically happens after the primary alcoholic fermentation and is guided by conditions that favor the bacteria. The result is a reduction in overall acidity and a rounder mouthfeel, often with subtle flavor notes like butter or cream from diacetyl formation. In Champagne and other sparkling wines, winemakers may allow or suppress MLF depending on whether they want extra softness and different aromatics or a brighter, crisper profile. It’s not about turning sugars into alcohol, nor about turning lactic acid back into malic acid, nor about converting acids into esters.