微生物法测定功能性饮料中维生素B12含量研究

该文建立了测定功能性饮料中维生素B12含量的微生物法.参考食品安全国家标准GB 5413.14—2010婴幼儿食品和乳品中维生素B12的测定方法，利用莱士曼氏乳酸杆菌生长速率与B12浓度的线性关系，制备标准曲线，根据标准曲线计算样品中B12的含量.根据功能性饮料与奶粉基底不同，对国标法中样品处理进行优化改良，同时实验中进行了加标回收对实验过程进行质量控制，并使用试剂盒法对测定结果进行比对.该方法操作简便，灵敏性及准确性高，可适用于功能性饮料中维生素B12含量的检测.

Study on determination of vitamin B12 in functional beverage by microbiological method

The determination of vitamin B12 is one of the most challenging problems in food analysis worldwide. A new method for detecting vitamin B12 in functional beverages was established. With reference to the determination method of vitamin B12 in infant foods and dairy products in the national food safety standard GB 5413.14－2010， which stems from the linear relationship between the growth rate of Lactobacillus leishmanii and B12 concentration， the standard curve was constructed and the content of vitamin B12 in samples were measured. Due to the differences among the substrates of functional beverages and milk powder， sample treatment methods were optimized based on the national standard. In addition， the quality control by standard additional recovery was conducted and the test result was compared with commercial assay kit. These results indicated that this method is able to be applied to the determination of vitamin B12 in functional beverages because of its simplicity， sensitivity and accuracy.