This process (also referred to as wet improvement) is also known as gallisation after the inventor Ludwig Gall (1791-1863). This refers to the addition of dry sugar (sucrose) dissolved in water to the grape must before or during fermentation. Fermentation of this sugar increases the alcohol content of the wine and reduces the proportion of titratable acids. However, using water as a solvent also increases the water content. The use of sugar water was subject to maximum limits in Germany. Wet sugaring was banned in Germany by the 1971 Wine Act, but was permitted until 1975 under transitional regulations; in Austria it had always been prohibited.
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)