METHOD DEVELOPMENT FOR THE SIMULTANEOUS DETERMINATION OF CARBOXYLIC-ACIDS, PHENOLIC-COMPOUNDS, AND SORBIC ACID IN WHITE WINES

A reversed phase liquid chromatographic method was developed for the s imultaneous determination of carboxylic acids and phenolics in white w ines. The samples, diluted, were injected onto a Spherisorb ODS-2 colu mn with a gradient of sulfuric acid (pH 2.5)/methanol as mobile phase. A diode array detector was used which was set at 210nm for carboxylic acids and altered to 278nm, during the run, far phenolics and sorbic acid. The identification of compounds was based on retention time, co- chromatography and UV spectrum. Some clean-up methods (sep-pak C-18 an d an ion exchange column) mere tested and did not improve the results. The analysis was simple, with no sample preparation. Application of t his method was illustrated by analyses of Brazilian Welchriesling wine s.