Glossary
Residual sugar (RS)
Measured in grams per litre. A bone-dry wine has under about 4 g/l; an off-dry wine 10–30 g/l; Sauternes can exceed 120 g/l and PX sherry 400 g/l.
In more detail
High acidity makes sugar taste less sweet, which is why a high-acid Riesling with 40 g/l can taste refreshing.