国标法测定特医食品中叶酸的方法研究  

Research on Determination of Folic Acid in Special Medical Foods by Microbial Method

作　　者：于瑞莉 任静 华佳淼 邹凤 黄丽俊 YU Rui-li;REN Jing;HUA Jia-miao;ZOU Feng;HUANG Li-jun(Wuxi Food Safety Inspection and Test Center/Technology Innovation Center of Special Food for State Market Regulation)

机构地区：[1]无锡市食品安全检验检测中心,国家市场技术创新中心(特殊食品)

出　　处：《中国标准化》2024年第15期251-256,共6页China Standardization

基　　金：国家市场监督管理总局科技计划项目“特殊食品中维生素类物质的单克隆抗体制备与超灵敏免疫定量分析技术研究”(项目编号:2022MK043)资助。

摘　　要：目的:研究不同储备菌株培养时间,检测体系培养时间、样品稀释倍数以及试样本底空白对特殊医学配方食品(简称特医食品)检测结果的影响。方法:比较储备菌株培养24 h和48 h后制备的种子液进行检测后结果的差异;比较标准曲线和试样系列管培养20 h后,每间隔2 h吸光度值的变化和检测结果的差异;比较样品进行0.5 f、f、2 f稀释后检测结果的差异;比较是否扣除试样本底空白对检测结果的影响。结果:储备菌株活化24 h测得质控样平均值为97.2μg/100 g,储备菌株活化48 h测得质控样平均值为106μg/100 g;培养时间20~38 h内,质控样检测结果标准差为5.37%,符合给定的数值范围;稀释倍数对结果的影响跟样品基质相关;试样本底空白对检测结果有影响,建议当本底空白A540超过0.05时,结果处理时扣除本底空白。结论:建议使用活化48 h的储备菌株制备种子液,检测体系培养时间可根据接种液浊度选择培养时间,推荐对按照标签值的1.5 f进行稀释,并在结果处理时根据需要扣除试样本底空白。Objective:The influence of culture time of different reserve strains,culture time of test system,dilution ratio of samples,and blank samples on the test results of foods for special medical purposes(FSMPs)was investigated.Methods:The results of seed liquid prepared after 24 h and 48 h were compared.After 20 h of tube culture,the change of absorbance value and the difference of test results of standard curve and sample series was compared every 2 h;the results were compared after 0.5 f,f and 2f dilution.And the influence of blank sample deduction on result processing was compared.Results:The average quality control sample of the reserve strain was 97.2μg/100 g after activated for 24 h and 106μg/100 g for 48 h.Within 20~38 h of culture,the standard deviation of quality control samples was 5.37%,which was in line with the given folic acid range.The influence of dilution ratio on the results was related to the sample substrate.Sample blank has an effect on the test results.It is suggested that when the background blank A540 exceeds 0.05,the background blank should be deducted in the result processing.Conclusion:It is recommended to use activated reserve strains for 48 h to prepare seed liquid.The culture time of the detection system can be selected according to the turbidity of the inoculate liquid.It is recommended to adopt the 1.5f dilution value according to the label,and the influence of blank samples should be deducted during result processing accroding to the need.

关 键 词：特医食品 国标法 叶酸 

分 类 号：TS207.3[轻工技术与工程—食品科学]