Indices of sugar—acidity as ripeness criteria for winegrapes

Abstract

Abstract Requirements for ripeness criteria of grapes for the making of dry table wine are considered, using measurements of sugar and acidity. The performance of indices was assessed by using averages of ‘optimum’ values of musts for top‐quality dry‐white and dry‐red table wines obtained from a survey of prominent South Australian wine‐makers. The defects of the ºBrix: titratable acidity ratio point to the need for an index which combines ºBrix and pH. ºBrix × pH leads to a large spread of pH values at extremes of ºBrix, while Brix:H+ gives an unrealistically narrow pH range. Brix × pH 2 appears to be an acceptable compromise.