This wine is being racked, the process of separating the clear, fermented wine from the sediment that has settled to the bottom of the barrel.
Racking: To avoid bottling a cloudy wine, the wine must be separated from the lees, or sediment. Once the lees have settled to the bottom of the barrel or tank, the clear wine on top is simply transferred into another vessel, leaving the sediment behind.
Fining: If some particulates remain suspended in the wine, the wine can be clarified, or fined, by adding fining agents such as bentonite (powdered clay) or egg whites to the top of the tank. The fining agents act like magnets, grabbing the oppositely charged suspended particulates as they settle to the bottom of the tank. The clear wine on top is then racked off the sediment.