Metatartric acid effects on the tartric acid less soluble salts, were studied in Riesling 1963, Riesling 1964 and Muscat of Alexandria 1965 wines, which showed progressive precipitations of potassium bitartrate and calcium tartrate in previous analysis. The esterification index of the acid was 33,5%.
Salts precipitation was not present when treated samples were stored for 90 days at -2°C. Metatartric acid concentrations between 3,0 to 100 mg/liter gave the same results.
Previously stabilized or with protide content wines, became turbid with metatartric acid agregations.