Simultaneous Determination of Sorbic Acid and Benzoic Acid in Soy and Vinegar by Derivative Ratio Spectrum Methods

s:This article introduces the modified method for simultaneous determination of sorbic acid and benzoic acid in soy and vinegar by Derivative Ratio Spetrum. Samples were extracted by acetic ether and stripped by Na 2HPO 4 Derivative Ratio Spectrum calculation was undertaken after five absorption values were measured at different wavelengths. The content of sorbic acid and benzoic acid in soy and vinegar were analysed. The recovery percent was between 96.25% ～102.25%. This method is simple and accurate compared with Kalman filtering and Multi-Wavelength Linear Regression UV-spectrophotometry. it can be used for determination of Sorbic acid and Benzoic acid in food.