Abstract:
A method based on the gel permeation chromatographic (GPC) clean-up and gas chromatographic separation has been developed to detect 7 preservatives, i.e., sorbic acid, benzoic acid, dehydroacetic acid, methyl p-hydroxybenzoate, ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate and butyl p-hydroxybenzoate, in soy sauce. Samples were extracted with diethyl ether, cleaned up by GPC, separated on a capillary column (Rxi-17, 30 m×0.25 mm×0.25 μm) and deteted with a FID. The linear range of the determination was 10.0~400.0 mg/L and the linear correlation coefficients of 7 preservatives were not lower than 0.9996. The detection limits (3S/N) of this method were 0.58~0.79 mg/kg. The recoveries ranged from 90.7%~99.1% with RSD (n=6) of 1.5%~4.2%.