Fining: A technique for clarifying wine using agents such as bentonite (powdered clay), isinglass (fish bladder), casein (milk protein), gelatin or egg whites, which combine with sediment particles and cause them to settle to the bottom, where they can be easily removed.
Bentonite: A clay compound used in the fining process of white wines. The clay binds with solids that might otherwise cause a white wine to become cloudy, removing them from the wine, although some molecules that would contribute to the wine's flavor profile are also removed in the process.
Gelatin: The same active gel found in Jell-O, this animal product is used in the fining process to bind with excess tannins so that they may be removed during filtration.
Isinglass: A protein-rich substance derived from the swim bladders of sturgeon and other fish and used in the fining process to improve clarity, color, mouthfeel and expression of fruit and to reduce astringency. Protein in the isinglass binds with excess tannins and other polyphenols and causes them to settle to the bottom, where they can be easily removed.
Fined: See Fining