Description for a negatively bitter and edgy taste (also tinny, hard, inky) of a wine in the context of a wine attack. High metal contents of aluminium, iron, copper or zinc in the wine can cause the wine defects black break (metallic taste) and white break. The wine can show a flaky turbidity from a milky-white to a blackish-green colour, which is why it is also called metal turbidity. The metals may have already entered the grapes from the vineyard soil or through fungal attack, or they may have been dissolved out of barrel nails by the influence of acids and tannins during barrel ageing. Some of this (iron, copper) can be removed by fining (blue fining). Also, when opening a bottle, contact of the corkscrew spiral with the wine can lead to a metallic note. Wines with a mineral flavour tone may also have very slight metallic tones, but in this case these do not signify a wine fault. Metallic must also not be confused with the positive term steely.
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)