At the end of the fermentation process and before bottling, the winemaker must proceed to the fining stage, which removes all impurities hung in the wine thus clarifying it. For this process, the winemaker makes use either of animal proteins (gelatine, casein, egg white) or vegetable proteins (wheat, potato, peas). The method most common for the fining is to place beaten egg white directly in the barrel. The egg white agglomerates the micro-particles, sticks them together, precipitating them to the bottom. The fining stage lasts for about twenty days before filtering, or racking, the wine.