顶空-气相色谱法测定婴幼儿配方食品和辅助食品中亚硝酸盐

Determination of Nitrite in Infant Formula Food and Supplementary Food for Infants and Children by Headspace Gas Chromatography

探究并优化顶空-气相色谱法检测婴幼儿配方食品和辅助食品中亚硝酸盐(以亚硝酸钠计)。样品经不同的前处理后,采用顶空-气相色谱仪进行测定,并采用外标法进行定量。亚硝酸盐可在1.7 min左右实现有效分离,并且在浓度范围内标准物质曲线线性良好,R2为0.9997。取样量为1.25 g时,对应的检测范围为0.03~18.58 mg/kg。该方法检出限为0.03 mg/kg,精密度在1.05%~5.98%之间。在常温超声30 min的条件下婴幼儿配方食品和辅助食品样品中亚硝酸盐提取最充分,加标回收率在94.37%~104.14%之间,相对标准偏差(RSD)均低于9.03%。该方法操作简便,稳定性好,检出限低,线性范围宽,重复性和回收率好,为实现快速检测婴幼儿配方食品和辅助食品中亚硝酸盐的研究提供参考。

To explore and optimize a headspace gas chromatography method for the determination of nitrite in infant formula food and supplementary food for infants and children was studied.After different pretreatment,the samples were determined by headspace gas chromatography and quantified by external standard method.Nitrite were effectively separated at about 1.7 min and good linearity of standard material standard curve was obtained in the certain concentration range,R2 is 0.9997.Moreover,the corresponding detection range was 0.03-18.58 mg/kg when 1.25 g sample was used.The detection limit of this method was 0.03 mg/kg,and the accuracy were between 1.05%and 5.98%.Under the condition of ultrasonic for 30 min at normal temperature,the nitrite extraction from milk powder samples is the best,satisfactory standard addition recovery rate were obtained in the range of 94.37%-104.14%,with relative standard deviation(RSD)lower than 9.03%.It provided a good reference for the rapid detection of nitrite in infant formula food and supplementary food for infants and children,with simple operation,good stability,low detection limit,wide linear range,and good repeatability and recovery rate.