Also referred to as residual sweetness (RS) sugar in the wine, by a natural end of the fermentation or through a targeted stopping (by cooling or by adding sulfur or alcohol). The residual sugar consists mainly of fructose (Fructose), because the glucose (Glucose) faster in alcohol and carbon dioxide and, to a lesser extent, non-fermentable sugars ( pentoses ). The remaining sugar content (dry to sweet) may be regulated by wine law on the optional label be specified. The phenomenon that the subjective perception of sweetness in wine, especially in the case of high acidity, can be relatively different from the actual analysis values, is below sweet described.
For sparkling wines apply due to the content of carbonic acid other residual sugar values and partly also other terms than at Still wines, In general, a wine contains depending on the expansion or type of wine between 4 and 50 g / l residual sugar, for certain sweet wines this can go up to 250 g / l (at Tokaj Eszencia even up to incredible 450 g / l). The residual sugar is incidentally in the aging or. bottle aging a wine is not broken down. Under ideal fermentation conditions (warm fermentation), a wine can ferment to a residual sugar content of 0.7 g / l. Complete fermentation to 0 g / l is not possible under natural conditions, as residues always remain non-fermentable sugars. Therefore, even a dry wine still contains a small amount of sugar. Wines with a content of less than 4 g / l are considered "completely fermented" (very dry). The salary can also be through sweetening (Addition of sugar in various forms) are increased in accordance with statutory provisions.
By residual sugar can be an unwanted bottle fermentation triggered or unwanted acetic acid and carbon dioxide be formed. This is done by previous filtration (Removal of yeasts) or pasteurization prevented. In a wine analysis, the residual sugar in g / l as reducing sugar determined. The wine regulated sweetening Wine is called residual sweetening. In contrast, the addition of sugar for the purpose of increasing the alcohol content is called enrich, The procedures for the determination of the residual sugar content are under sugar content cited. For the other ingredients in wine, see total extract,
Complete listings of the numerous vinification measures and cellar techniques, as well as the various wine-regulated wine, sparkling wine and distillate types are under the keyword winemaking contain. Comprehensive information on wine law is available under the keyword wine law,