malolactic fermentation

Malolactic fermentation is a bacterial process that occurs in winemaking. It involves the conversion of malic acid, which has a sharp, tart taste, into lactic acid, which is softer and smoother. This transformation is carried out by lactic-acid bacteria, often Lactobacillus or Pediococcus species, which produce enzymes to facilitate the reaction.123

This secondary fermentation can be desirable to reduce excessive acidity in wines, particularly those from cooler climates, or to impart specific flavor nuances. However, it can also lead to undesirable outcomes like flat taste or off-odors if not managed properly. Factors such as temperature and the presence of sulfur dioxide can influence the rate and success of malolactic fermentation.24