Description (also drying or unripe tannins or tannins) for the negatively understood mouth-drying, rough or strongly astringent effect in the context of a wine address. However, this is not a gustatory, but a trigeminal (involving the sense of touch) sensory impression. These are particularly fine-grained tannins that give an impression of fine sand in the mouth and taste rather unpleasantly "edgy". They are also called "bad tannins". As a rule, this does not change even if the wines are matured for a longer period of time. The cause is unripe grapes. In contrast, the "good or ripe tannins" are coarse-grained and give a "soft" impression. There is an original way to check whether the tannins are "good" or "bad". If you can whistle after tasting a wine with tannins, they were "good" ones. Another characteristic is that they stimulate salivation. A term used in the USA for a too pronounced tannin taste is tannin to lose.
For me, Lexicon from wein.plus is the most comprehensive and best source of information about wine currently available.Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)