婴幼儿米粉中菌落总数检测方法的比较

Comparison of detection methods of total bacterial colonies in infant rice flour

中文关键词:  婴幼儿米粉  菌落总数  检测方法

英文关键词:infant rice cereal  aerobic plate count  detection method

中文摘要:

      目的 比较5种不同方法检测婴幼儿米粉中菌落总数的检测效果, 确定最优的检测方法。方法 采用PCA直接倾注法、添加2,3,5-三苯基氯化四氮唑(2,3,5-triphenyltetrazolium chloride, TTC)方法、无菌滤网过滤基质方法、倾注后覆盖法、试纸片法分别测定10种婴幼儿米粉中的菌落总数。结果 5种方法检出率顺序为倾注后覆盖法＜PCA直接倾注法＜添加TTC法、试纸片法＜无菌滤网过滤法。倾注后覆盖法较PCA直接倾注法能有效地抑制容易蔓延生长的需氧细菌, 但两者受米粉基质的影响较大。添加TTC法能降低米粉基质对计数结果的干扰, 采用试纸片法能减少米粉基质和米片对计数的影响, 但两者都抑制平板中部分革兰氏阳性菌的生长, 导致计数结果偏低。采用无菌滤网过滤法能有效地消除米粉基质与米片的干扰, 且不受TTC对菌落的抑制因素影响。结论 在对婴幼儿米粉的菌落总数检测中, 无菌滤网过滤法优于其他4种方法。

英文摘要:

      Objective To compare the detection effects of 5 kinds of different methods on the total number of colonies in infant rice cereal, and determine the best detection method. Methods The total number of colonies in 10 kinds of infant rice cereal were detected by 5 kinds of methods respectively, including pouring plate count agar directly, adding 2,3,5-triphenyltetrazolium chloride (TTC), sterile strainer filtering method, covering a layer of agar medium and 3M petrifilm plates method. Results The detection rate order of the 5 methods was the post-dumping method