婴幼儿乳品中叶酸的微生物测定方法

Studies of Microbiological Assay Folic Acid in Infant Milk

按照GB 5413.16-2010、GB/T 5009.211-2008及Biostest叶酸检测试剂盒等不同方法,对同一乳制品样品叶酸含量进行测定,同时进行加标回收试验。结果表明,依据GB 5413.16-2010,在制备标准测试管时,使用两种浓度的含抗坏血酸的磷酸缓冲液稀释获得的叶酸标准工作液,同时样品测试液也由抗坏血酸的磷酸缓冲液稀释获得,测得叶酸质量分数为40.45μg/hg,回收率为71%。而参照GB/T 5009.211-2008,只使用一种浓度的用水稀释获得的叶酸标准工作液,同时样品测试液也由水稀释获得,测得同一样品的叶酸质量分数为70.5μg/hg,回收率为92.6%。使用Biostest叶酸检测试剂盒测得同一样品的叶酸质量分数为73.71μg/hg,回收率为99%。不采用含抗坏血酸的磷酸缓冲液而是用水稀释获得标准工作液和样品测试液,测试婴幼儿乳制品叶酸含量,加标回收率较高,测试结果可以接受。

According to the GB 5413.16 2010, GB/T 5009.211 2008 and Biostest different methods, On the same folic acid content in dairy products and for folic acid determination of standard addition recovery experiment was carried out at the same time. Results show that according to GB 5413.16 2010,in the preparation of standard test tube,using two concentration with phosphate buffer containing ascorbic acid dilution folic acid standard working liquid,liquid sample tests also diluted by ascorbic acid phosphate buffer,naeasured tblic acid content is 40.45 μg/100 g,the recovery was 71%. But GB/T 5009.211 2008,using only a concentration of diluted fblic acid standard working liquid, liquid sample tests also get diluted by water, measured the same samples of folic acid content is 70.5μg/100 g,the recovery was 92.6%. Using Biostest folic acid detection kit measured the same samples of folic acid content is 73.71 μg/100 g,the recovery was 99%. Conclusion is not using ascorbic acid in phosphate butler but diluted standard working liquid and liquid sample tests,testinfant dairy folic acid content,the standard addition recovery rate is higher,test results are acceptable.