The juice of the grape ( grape must ), extracted from the grapes by pressing, is transformed into wine. During this chemical reaction, yeast splits the sugar into alcohol and carbon dioxide. Before it results in the final product wine, it can be drunk as Federweißer. This process is called fermentation. The fermantation starts with its "Wild" (teen-stormy") part, which lasts about eight days. These wild days are then followed by the "silent" part, which lasts about three weeks. During this time, one can smell the young wine in the wine villages and hear it "bubbling" in the cellar.