奶制品中亚硝酸盐含量的测定

Determination on Content of Nitrite in Milk Products

采用盐酸萘乙二胺分光光度法对奶制品中的亚硝酸盐含量进行了测定。系统考察了重氮化试剂和显色剂用量、重氮化反应和显色反应的反应时间等对测定灵敏度的影响,并优化了仪器的测量条件。实验结果表明,在最佳实验条件下,以λ=540 nm为测定波长,亚硝酸盐在0～0.2μg/L内线性良好,相关系数为0.999 7。奶制品样品加标回收率在100%～105%之间。该方法灵敏度高、操作简便,值得推广。

The content of nitrite in milk products was determined by spectrophotometry method with hydrochloric acid naphthalene ethylenediamine as the color reaction reagent.The factors that affected the sensitivity were investigated,in-cluding the quantity of diazotization reagent and color reaction reagent,the time of diazotization reaction and color reac-tion.Under the optimized conditions,the linearity was ranged in 0～0.2 μg/L（r =0.999 7） with the detection wavelength of 540 nm.The spiked recoveries were ranged from 100 % to 122.8%.The poposed method had the characters of high sensitivity,simple operation and worth application.