Improper use of copper-containing agents can lead to cloudiness in the wine and a metallic-bitter taste or the wine defect black fracture; see there.
The wine defects white fracture (grey fracture), black fracture and partly also brown f racture are closely related in terms of causes and effects. During the vegetation period, the vine also absorbs various metallic trace elements through the roots. These are aluminium, lead, iron, copper, silver and zinc. During winemaking, these substances, known as primary, natural metals, are greatly reduced. However, improper or...
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Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)