A gradient elution/ion exchange chromatographic method was developed for the simultaneous determination of lactic acid,acetic acid,DL malic acid,malonic acid,maleic acid,oxalic acid,citric acid and DL-isocitric acid trisodium salt in fruit juice.0.8-30 mmol/L KOH was produced with an EG40 eluent autogenerator.Eight organic acids were separated on an IonPac AS11-HC column and an IonPac AG11-HC guard column,and detected with suppressed conductivity detector under the self-regenerating suppressor mode.The gradient elution conditions were optimized.Under the optimal conditions,eight organic acids were successfully separated and good linear relationships were obtained between peak area and mass concentration in the measurement ranges.The detection limits were in the range of 10-30 μg/L,and the average recoveries were 95%-100% with RSDs(n=6) less than 3.0%.The method was simple and was applied in determination of eight organic acids in fruit juice samples with good precision and accuracy.The method could be used to evaluate the quality of fruit juice by developing fingerprint chromatograph of squeezing fresh fruit juice.
关键词
离子交换色谱淋洗液自动发生有机酸果汁饮料
Keywords
ion exchange chromatographyeluent autogenerationorganic acidsfruit juice