A preparation artificially produced from the plant product gum arabic and citric acid. By adding it to the wine, the reaction of metals with ingredients of the wine and thus a precipitation of copper or iron and thus a metallic taste is prevented. This can prevent wine defects such as white curd and black curd. In addition, the precipitation of colouring agents is also prevented and wines with a strong tannin content are mellowed. See also under Beautiful at the section blue fining.
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Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)