The Use of PVPP for Decolorizing Wine in the Determination of Tartrate by the Metavanadate Method

Abstract

The decolorization of red wines is required for the colorimetric determination of tartaric acid by the metavanadate method. The use of charcoal as the decolorizing medium is time consuming. A method is described using a column (7 mm ID and 22 cm long) packed with 0.5g coarse PVPP (Polyclar AT). The method renders the wine colorless. Comparison of the charcoal and PVPP decolorizing methods indicated the charcoal can cause variations in the tartrate concentration dependent upon the previous treatment of the charcoal, while PVPP yielded colorimetric results similar to the standard solutions. Studies using red wine which had been previously deacidified by ion exchange and known concentrations of tartaric acid added were analyzed by both methods.