Residual sugar

Residual sugar meaning in wine

Residual sugar (RS) is sugar present in the finished wine after fermentation and any permitted finishing operations. Grape must contains mainly glucose and fructose; yeast converts fermentable sugar into ethanol, carbon dioxide, and other products, but the finished amount varies with the wine and the production choices allowed by its rulebook.

“Residual sugar” is often used conversationally for one g/L number, but the analytical definition matters. The OIV still-wine categories cited in this glossary use glucose + fructose. Current EU sparkling-label terms use sugar expressed as fructose, glucose, and sucrose. Those are related systems, not wording to combine casually.

Residual sugar is not perceived sweetness

A laboratory result tells you composition. It does not guarantee that every drinker will report the same sweetness intensity. Acidity can suppress sweetness; aroma, alcohol, bitterness, astringency, carbonation, temperature, and context can also affect the overall impression.

Dry wine therefore does not have to mean zero sugar, and one measured value should not be converted into a universal tasting verdict without the wine type and applicable rule.

Use the wine sweetness chart for the OIV still-wine categories, the separate EU sparkling terms, and their acidity and overlap conditions. See fermentation for the process definition.