Spectrophotometric determination of total procyanidins in wine vinegars

A widely-used method for the spectrophotometric determination of procyanidins in wines has been adapted to wine vinegar samples. Reagent concentrations have been established and the analytical method tested for possible matrix effects. The recovery of catechin was approximately 98% and the limit of reliable measurement was 0.48 mg l(-1). The within-day and between-day precisions were evaluated and according to the two-tailed F-test the precisions were statistically equivalent. Application to wine vinegars obtained by traditional and quick acetification methods showed differences in concentration between the two groups.