High-performance Liquid Chromatography for Determination of BenzoicAcid and Sorbic Acidin in Soybean paste and salted vegetable

A method for the determination of sorbic acid and benzoic acid in Soybean paste and salted vegetable was established．The sample was mashed at a high speed meanwhile sorbic acid and benzoic acid was extracted by diethyl ether．The fat in the sample would be removed by changing the pH of the liquor．Sorbic acid and benzoic acid were detected by HPLC．Using C18 stainless column with methanol-Ammonium acetate (5∶95,V/V) measure sorbic acid and benzoic acid,detection wave length was 230 nm．The limit of detection(LOD)were 0.3 mg／kg for benzoic acid and 0.25 mg／kg for sorbic acid．The recovery was between 94.1%~105.0% and the relative standard deviation was between 1.3%~2.1% ．