婴幼儿配方乳粉菌落总数检测与细菌污染种属分析

Determination of total bacterial colony and analysis of bacterial contamination species in infant formula milk powder

目的考察婴幼儿配方乳粉的微生物污染情况,分析婴幼儿配方乳粉的菌相构成。方法采用国标方法测定30批次1段、2段、3段婴幼儿配方乳粉菌落总数,使用基质辅助激光解吸电离飞行时间质谱对检出的优势菌落进行鉴定。结果30批次婴幼儿配方乳粉的菌落总数均符合国家限量要求,其中1段乳粉菌落总数显著性低于2段和3段乳粉(P<0.05)。婴幼儿配方乳粉中检出的细菌主要为芽孢杆菌属、类芽孢杆菌属、球形芽孢杆菌属、肠球菌属、葡萄球菌属和链球菌属,其中芽孢杆菌属检出率最高。此外,9批次样品中检出蜡样芽胞杆菌。结论我国婴幼儿配方乳粉质量仍存在一定的风险,监管部门应加强日常监管工作。

Objective To investigate the microbial contamination of infant formula milk powder and analyze the bacterial composition of infant formula milk powder.Methods The total number of bacterial colonies of 30 batches of infant formula milk powder in 1,2 and 3 stages was determined by national standard method.The dominant bacterial colonies detected were identified by stroma-assisted laser desorption ionization time-of-flight mass spectrometry.Results The total number of bacterial colonies in 30 batches of infant formula milk powder met the national limit requirements,and the total number of bacterial colonies in the first stage of milk powder was significantly lower than that of the second and third stages of milk powder(P<0.05).The bacteria detected in infant formula milk powder were mainly Bacillus,Paenibacillus Ash,Bacillus sphaericus,Enterococcus,Staphylococcus and Streptococcus,among which Bacillus had the highest detection rate,and Bacillus cereus was detected in 9 batches of samples.Conclusion There are still some risks in the quality of infant formula milk powder in China,so the supervision department should strengthen the daily supervision.