Determination of Tartaric Acid in Wine

Abstract

Tartaric acid analyses (metapervanadyl tartrate color complex) of wines and tartaric acid standard solutions decolorized by carbon treatment were compared with those of samples decolorized by passage through a column containing an adsorptive resin. Recovery of tartaric acid (2000 mg/liter) added to a wine stripped of organic acids by anion-exchange treatment was more accurate when the wine decolorizing was by the resin treatment (99.6%) than by the carbon treatment (105.9%). Standard solutions of tartaric acid gave statistically the same color absorbance values when determined as untreated samples or resin-treated. Carbon treatment of standard solutions gave lower results, with absorbance decreasing with increasing concentration of carbon. Tartaric acid concentration of wines decolorized with different levels of carbon and calculated from comparison with tartaric acid standards treated with the equivalent carbon levels gave different results. Wines decolorized by the resin treatment resulted in lower concentrations of tartaric acid compared to the results of the same wine decolorized by the carbon treatment. Thus, results for tartaric acid in wines decolorized by the carbon treatment are questionable, whereas results in wines decolorized by the resin treatment are more accurate.