生乳中亚硝盐回收率检测分析研究

目的 改进国标中因生乳本底对回收率结果的影响。方法 依据GB 5009.33-2016《食品中亚硝酸盐与硝酸盐的测定》中第二法分光光度法, 在加标回收实验中将生乳本底进行不同倍数稀释, 确定回收率最佳时的稀释倍数。结果 对生乳本底进行稀释后, 确定10倍稀释后加标回收率全部符合要求, 最大相对标准偏差为9.118%。检测实际样品时, 本方法与国标检测结果经无显著性差异(P=0.10)。结论 改进后的方法操作简单, 回收率高、准确性高, 可用于牛乳中亚硝酸盐的检测。

Detection and analysis of nitrite recovery in raw milk

Objective To improve the influence of raw milk background on the recovery rate in the national standard. Methods According to GB 5009.33-2016 Determination of nitrite and nitrite in food in the second method spectrophotometry, the raw milk background was diluted by different multiples in the standard recovery experiment to determine the dilution ratio when the recovery rate was the best. Results After 10 times dilution, the standard recovery rates could meet the requirements, and the maximum relative standard deviation was 9.118%. When the actual samples were tested, there was no significant difference between this method and the national standard test results (P=0.10). Conclusion The improved method has the advantages of simple operation, high recovery and accuracy, and can be used for the determination of nitrite in milk.