摘要
微量扩散法是测定肉品TVB-N含量的国家食品卫生标准检验方法。该法作空白试验时,指示剂呈色反应不明显,样品检验的滴定终点较难控制,致使重现性较差,通过对指示剂等加以改良后,克服了上述缺点。经试验结果表明,改进后的方法法变异系数为1.19%,标准差为±0.089,精密度优于原法;用已知铵氮标准溶液加入样品,测得的平均相对误差为—0.625%,准确度符合要求;与经典的半微量定氮法比较,两者无显著差异,适于在基层中推广使用。本文同时提出了验证本法准确度的简易方法。
Micro-diffusion method is the second method for testing the totalvolatile basic nitrogen (TVB-N) of meat products in the national food hygienestandards, it has the advantages of simple appliance and easy manipulation.But with this method, the coloured reaction of indicator was not clear in thecontrol test, controling the terminal of titration in the sample tests was diff-icult, so that the repeatability is not good. After improving the indicator andso on, the original shortages have been overcome. The test indicated that, usingthe improved method, the average relative error of sampling is -0.625%with osatisfied accuracy, the variation coefficient is 1.19%, standard difference is±0.089, the precision is higher than the original method. There are no signific-ant difference between the improved method and the classic semi-micro nitrogendetermination (P>0.05). The improved method can be used and extented inpractice. The simple method of evaluating the accuracy of the improved methodwas also developed.
关键词
猪肉
微量扩散法
挥发性
盐基底
pork, food defection
food standard/micro-diffusion method
total volatile basic nitrogen
