Unit of measurement for the value or scale (potentia Hydrogenii = strength concentration of hydrogen) for the concentration of active acids in a solution, which is measured using the free hydrogen ions. In viticulture, this is an important criterion for the growth of the vine, the ripening of the grapes and the taste and shelf life of the wine. The content of the soil (from alkaline to acidic), the temperature and the amount of precipitation during the vegetation cycle as well as the grape variety are of great importance with regard to the concentration in the wine. In connection with winemaking, the degree of acidity (acidity) in the soil and in a wine is expressed. Although this is related to the acidity in the wine (sum of different acids), it says something completely different.
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