M. Castellari et al., An improved HPLC method for the analysis of organic acids, carbohydrates, and alcohols in grape musts and wines, J LIQ CHR R, 23(13), 2000, pp. 2047-2056
An improved high performance liquid chromatography (HPLC) method for the an
alysis of the main organic compounds in musts and wines is presented. A col
umn packed with hydrogen sulfonated divinyl benzene-styrene copolymer and t
wo detectors connected in series were used (UV at 210 nm and RI, respective
ly). The addition of acetonitrile (6%) to the mobile phase (0.045N H2SO4) a
llowed the simultaneous separation and quantification of several organic ac
ids, glucose, fructose, glycerol, and ethanol. Direct injection and sample
clean-up with a SAX cartridge was tested and compared. The SAX fractionatio
n gave satisfactory results, however the direct injection of diluted wine (
1:20) provided the best precision (CV less than or equal to 2.1%) and accur
acy of analysis. Statistical analysis (paired t-test) disclosed significant
differences only for glucose, fructose, alpha-ketoglutaric, and pyruvic ac
id. 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 greater than or equal to 30 degrees C.