Simultaneous determination of four organic acids in beverages by capillary electrophoresis coupled with ultraviolet detector

Abstract

A simple and rapid capillary electrophoresis method with direct ultraviolet (UV) detection was set up for the determination of four organic acids in beverages. The method included dilution and filtration as simple sample preparation steps. The electrophoretic separation and detection of oxalic, malic, citric and lactic acids in wines and beers were performed in 8 min. For the method validation, linearity, detection and quantification limits, repeatability and recovery in wine and beer matrices were studied. Good linearity was observed from 25 to 500 mg/L for all acids excluding lactic acid, for which it started from 50 mg/L. The limits of quantitation of oxalic, malonic and citric acid were set 9.5 to 28.5 mg/L. Repeatability of this method was from 3.2 to 7.3%, recoveries ranged from 90.1 to 110.1%. The validated method was applied to the analysis of different wines and beers and showed great variability in their composition.