Determination of Seven Organic Acids in Soy Sauce by Solid Phase Extraction-high Performance Liquid Chromatography

A new method for simultaneous determination of seven organic acids in soy sauce was developed with solid phase extraction – high performance liquid chromatography.The sample was purified by a Strata SAX SPE cartridge after pretreatment,then separated using a reversed-phase Agilent SB-Aq(150 mm×4.6 mm×5 μm)column.0.01 mol/L(NH4)2HPO4(pH 2.7) solution was used as the mobile phase at a flow rate of 0.7 ml/min.The detection was performed on an ultraviolet detector at 210 nm.The relative standard deviations were 0.13%~1.9% and the recoveries were 95.0%~105%.The correlation coefficients for the linear equations were 0.9993~0.9999.The results mentioned above indicated that the method was simple,rapid and accurate.It could be applied to the determination of organic acids in soy sauce.