- What are fining agents?
- How do fining agents work?
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; to either 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.
The How: Neutralising Charges
The electrostatic types comprise the vast majority. Their purpose is to selectively remove proteins, tannins (polyphenolics) and coloring particles (melanoidins). They must be used as a batch technique, as opposed to flow-through processing methods such as filters. Their particles each have an electric charge which is attracted to the oppositely charged particles of the colloidal dispersion that they are breaking. The result is that the two substances become bound as a stable complex; their net charge becoming neutral. Thus the agglomeration of a semi-solid follows, which may be separated from the beverage either as a floating or settled mass.
The How: Absorbtion
Although activated carbon may be implemented as a flow-through filter, it is also commonly utilized as a batch ingredient, which later must be separated and discarded from the beverage. It can completely/partially remove benzenoid compounds and all classes of polyphenols non-specifically, decolorizing and deodorizing juices and wines.
The How: Enzymes
The enzymatic finings are pectin and pectinase. They aid in destroying the large polysaccharide molecule named pectin,[clarification needed] which otherwise causes haze in fruit wines and juices. They are among the few finings that are added before juices are fermented.