Usually during this maceration, the fermentation process starts with ambient yeasts in the cellar. Often the wine will have fermented to the point where the grape spirits are added before maceration has ended and the wine is pressed off the skins, a process known as "mutage sur grains". The added alcohol during maceration allows for more ethanol-soluble phenolics and flavor compounds to be extracted. After pressing, the wine is left to settle in concrete vats over the winter before it is racked into barrels or other containers.