Designation (also back-up bottle, second bottle, counter-test bottle) for wine bottles provided especially for professional wine evaluations for a counter-test (counter-test) that may be necessary. If there is a suspicion of a bottle fault such as a cork taster, a back-up bottle (or a second bottle, if necessary) can be opened immediately and tasted for comparison. This can provide exact information as to whether a wine defect relates only to a specific bottle and whether this should be taken into account in the wine evaluation. The phenomenon that the same wine can have quality differences from bottle to bottle is called bottle variance.
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Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)