In German-speaking countries (Germany, Austria, Switzerland), a common designation for a certain content of residual sugar in the wine, which can optionally be indicated on the label. These are up to 4 g/l or up to 9 g/l, provided that the total acidity is at most 2 g lower than the residual sugar. This means that, for example, with 9 g/l residual sugar, the total acidity must be at least 7 g/l. This acidity regulation has a practical meaning, because with higher acidity the sweetness is perceived less. In the case of dry sparkling wine, where a clearly different taste sensation is given by the sparkling carbonic acid, the residual sugar may even be between 17 and 32 g/l (this means for still wine already medium sweet).
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