紫外光度法同时测定酱油中苯甲酸和山梨酸含量

Simultaneous Determination of Benzoic Acid and Sorbic Acid in Soy Sauce by UV Spectrometry

基于苯甲酸和山梨酸的紫外吸收光谱特性,采用多元线性回归法同时测定酱油中苯甲酸和山梨酸的含量。酱油经简单萃取分离,测定9个波长处的吸光度值后,进行回归计算分析。实验结果表明：该方法计算结果与高效液相色谱法测定结果 相对误差小于4.26%,苯甲酸和山梨酸的加标回收率为98.9%-102.6%。

Based on the UV absorption characteristics of sorbic acid （SA） and benzoic acid （BA）, the content of SA and BA in soy sauce is determined simultaneously by multi-wavelength linear regression UV spectrophotometer. The benzoic acid and sorbic acid are re-extracted with Na2 HPO4 solution from the ether,with which the soy sauce is extracted in acid solution. Regression calculation is undertaken after nine absorption values is measured at different wavelengths. The results show that the relative error is less than 4.26% when comparing the UV spectrophotometry with high performance liquid chromatography, and the average recoveries of benzoic acid and sorbic acid are 98.9%-102.6%.