Finings

Finings are substances that are usually added at or near the completion of the processing of brewing wine, beer, and various nonalcoholic juice beverages. Their purpose is for removal of organic compounds; either to improve clarity or adjust flavor/aroma. Specifically, the removed compounds may be sulfides, proteins, polyphenols, benzenoids, or copper ions. Unless they form a stable bottom sediment in the final container, the spent finings are usually discarded from the beverage along with the target compounds that they capture.

Historically, various substances such as egg whites, blood, milk, isinglass, and Irish moss have been used as finings. These are still used by some producers, but more modern substances have also been introduced and are more widely used, including bentonite, gelatin, casein, carrageenan, alginate, diatomaceous earth, pectinase, pectolyase, PVPP (Polyclar), kieselsol (colloidal silica), copper sulfate, dried albumen, hydrated yeast, and activated carbon.

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