荧光光谱法和紫外分光光度法在发酵调味品中苯甲酸含量测定中的应用和比较

Application and comparison of methods on determination of content of benzoic acid in zymotic flavoring by using fluorescent spectrometry and ultraviolet spectrophotometry

对紫外分光光度法和荧光光谱法测定酱油和食醋中苯甲酸含量的方法进行了优化和比较,实验结果表明,荧光光谱最佳发射波长为320 nm,最佳激发波长为225 nm,最佳测定pH为2.6;最优化样品氧化条件为水浴温度为100℃,蒸馏液体积为50 mL,水浴时间为17.5 min;荧光光度法在测定准确度、最低检测限和加标回收率以及检测的方便性都明显优于紫外分光光度法。

The methods for determining the content of benzoic acid in zymotic flavoring by using fluo- rescent spectrometry and ultraviolet spectrophotometry was optimized and compared in the study. The results showed that the optimal emission wavelength ,excitation wavelength and determining pH of fluorescence spectrum were 320 nm,225 nm and 2.6 respectively. The optimized oxidation conditions including waterbath temperature, distillate volumn and waterbath time were 100 ℃, 50 mL and 17.5 min. Fluorescent spectrometry execlled in accuracy, detection minimum limit and recovery addi- tion of standard compared with ultraviolet spectrophotometry.