An Improved HPLC Method for the Analysis of Organic Acids, Carbohydrates, and Alcohols in Grape Musts and Wines

M. Castellaria, A. Versarib*, U. Spinabellia, S. Galassia & A. Amatia a Università di Bologna , Facoltà di Agraria - Scienze e Tecnologie Alimentari, Villa Almerici - via Ravennate 1020, Cesena, (FC), 47023, Italy b Università di Bologna , Facoltà di Agraria - Scienze e Tecnologie Alimentari, Villa Almerici - via Ravennate 1020, Cesena, (FC), 47023, Italy * An improved high performance liquid chromatography (HPLC) method for the analysis of the main organic compounds in musts and wines is presented. A column packed with hydrogen sulfonated divinyl benzene-styrene copolymer and two detectors connected in series were used (UV at 210 nm and RI, respectively). The addition of acetonitrile (6%) to the mobile phase (0.045N H2SO4) allowed the simultaneous separation and quantification of several organic acids, glucose, fructose, glycerol, and ethanol. Direct injection and sample clean-up with a SAX cartridge was tested and compared. The SAX fractionation gave satisfactory results, however the direct injection of diluted wine (1:20) provided the best precision (CV ≤ 2.1%) and accuracy of analysis. Statistical analysis (paired t-test) disclosed significant differences only for glucose, fructose, α-ketoglutaric, and pyruvic acid. The role of column temperature for the analysis of vitamin C (ascorbic acid) was also investigated. Vitamin C underwent thermal degradation during analysis with column temperature ≥ 30°C.