基于离子色谱技术快速定量乳制品中亚硝酸盐的含量

本研究旨在建立离子色谱法快速测定乳制品中亚硝酸盐含量的分析方法。样品采用0.005 mmol/L NaOH提取，1∶1的乙腈-3%乙酸溶液作为蛋白沉淀剂，以1.8 mmol/L NaHCO3- 和1.2 mmol/L Na2CO3为淋洗液，流速为1.2 mL/min，分析柱为InoPacAS14，电导检测器检测。结果表明，亚硝酸盐的检出限为0.04 mg/kg，加标回收率为96.8%～99.4%，与国标GB/T 5009.33-2010中检测方法比较，相对偏差＜1%。方法简便，快速，用于乳制品中亚硝酸盐含量的测定结果满意。

Nitrite determination of in dairy products by ion chromatography technique

An analytical method was developed for nitrite determination in dairy products using ion chromatography. Samples were extracted with 0.005 mmol/L NaOH, and protein was precipitated by the mixture of acetonitrile and 3% acetic acid solution with ratio of 1∶1. The eluent was composed of 1.8 mmol/L NaHCO3- and 1.2 mmol/L Na2CO3, and the flow rate was 1.2 ml/min. The analysis was performed on Dionex AS14 separation column, and the conductivity detector was used for detection. Results showed that the detection limit was 0.04 mg/kg for nitrite. The recoveries tested by the standard additions method were in the range of 96.8% to 99.4%. The results was compared with the results of GB/T 5009.33-2010, the relative deviation was less than 1%. The method was simple, time-saving, and suitable for the determination of nitrite in dairy products.