Reduction or conversion of the acids contained in the wine through various measures. This is particularly necessary in poor wine years when the grapes have not reached a sufficient degree of ripeness. This is generally permitted for fresh grapes, grape must, partially fermented grape must, young wine and wine. However, this depends on the wine-growing zone. For wine-growing zone A (Germany, except Baden) and wine-growing zone B (Baden and Austria), partial deacidification is permitted (but not acidification). Although a high acid content in the grape must with a low pH value results in a purer fermentation, it is advisable from 12 g/l upwards.
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Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)