Allergenic potential of fining agent residues in German wines related to their dosage and an ordinary bentonite treatment

Fining agents, such as isinglass, gelatine, hen's egg-white, or caseins, are used for wine improvement since a long time. Because they are also known as important food allergens, their labelling has been regulated by Directive 2003/89/EC within the European Community. However, since no scientific data exist about their residue and allergic potential in wines, a temporary labelling exemption has been granted. In this report, we describe the influence of fining agent dosage and bentonite treatment onto the amount of fining agent residues in German wines. Fining agent proteins were measured by enzyme-linked immunosorbent assay (ELISA). Ominous residues of fining agents were found neither in wines treated with an ordinary nor in wines treated with an excess dosage of fining agents. Furthermore, ominous residues were found neither in wines with bentonite-treatment nor in wines without bentonite treatment.