fter the grapes have been crushed into must, the vinification continues with the following steps:
Alcoholic Fermentation
Grape musts consist of two main components, water and sugar, in solution with yeasts which multiply as they consume the sugars and convert them to alcohol while freeing carbon dioxide.
This complex biochemical phenomenon is characterized by violent bubbling that creates considerable heat. Fermentation was often known as bollitura, or boiling, when it took place in open wooden vats in Italy. Today, it is often conducted in closed stainless-steel or cement tanks at controlled temperatures. Modern white wines are usually fermented cool to retain fresh flavors and the so-called primary aromas from the grapes.
Drawing the wine off the lees
When the alcoholic fermentation has converted the must to wine, it is allowed to settle so that the solid matter - known as the lees - collects at the bottom of the tank. Then the wine is pumped off the lees to other containers to begin the next step.
Malolactic Fermentation
Most red wines, as well as some whites, undergo a gentle secondary fermentation induced by bacteria rather than yeasts. This malolactic fermentation transforms sharp-flavored malic acid into softer lactic acid, a process that lowers total acidity and makes wines seem rounder and fuller in flavor.
