Simultaneous determination of 11 organic acids in concentrated juices using SPE-reverse-phase high performance liquid chromatography
A method was developed for the determination of the tartaric acid,quinic acid,malic acid,shikimic acid,Vc,acetic acid,maleic acid,lactic acid,succinic acid,fumaric acid and citric acid in juices using reversephase high performance liquid chromatography.The sample was diluted by water and then was purified by C18 solid-phase extraction(SPE).Reverse-phase liquid chromatographic analysis was performed on the instrument of Agilent 1100 series equipped with a diodearray detector and autosampler.The column was Aichrom BondAQ C18(25 cm×4.6 mm,5 μm).The mobile phase was 0.02 mol/L NH4H2PO4(pH2.8)-Methanol(99:1,v/v) with a flow rate of 0.8 mL/min.The detection wavelength was 210 nm.The retention time for all of organic acids in the pear,apple,strawberry and pomegranate juices were less than 15 min after the samples treated by SPE.The calibration curve for the organic acids was in good linearity with a correlation coefficient of upwards 0.990.The recovery ratio of the organic acids was 85.1%~95.5% and the coefficient of variation was less 4%.The results indicate that this method is handy,fast,veracious and practical for the routine analysis of organic acids in juices.