4种方法测定矿泉水中产气荚膜梭菌测量审核结果的比较分析

Comparison and analysis of 4 methods for measuring and reviewing Clostridium perfringens in mineral water

中文关键词:  产气荚膜梭菌  矿泉水  测量审核  SPS培养基  TSC培养基  倾注上层培养基

英文关键词:Clostridium perfringens  mineral water  measurement audits  sulfite polymyxin sulfamethazine  tryptose sulfite cycloserine  pouring the upper medium

中文摘要:

      目的 比较分析4种方法对矿泉水中产气荚膜梭菌测量审核结果的影响。方法 以测量审核作业指导书、GB 8538—2016《食品安全国家标准 饮用天然矿泉水检验方法》为依据, GB 4789.13-2012《食品安全国家标准 食品微生物学检验 产气荚膜梭菌检验》为参考, 分别采用两标准中的亚硫酸盐-多粘菌素-磺胺嘧啶(sulfite polymyxin sulphadiazine, SPS)琼脂培养基和胰?-亚硫酸盐-环丝氨酸(tryptose sulfite cycloserine, TSC)琼脂培养基, 再以以滤膜法倾注上层培养基与不倾注上层培养基的方法同时检测测量审核样品和模拟水样。比较2种培养基的产气荚膜梭菌回收率, 运用方差分析测量审核样品、运用配对t检验模拟水样, 进而评价4种方法对矿泉水中产气荚膜梭菌计数结果一致性的影响。结果 4种方法检测结果无明显差异, 但是经不倾注上层培养基培养后目标菌难显黑色, 经倾注上层培养基培养后目标菌显黑色。3个厂家的SPS培养基、TSC培养基产气荚膜梭菌的平均回收率分别为: 89%、98%。采用TSC培养基和滤膜法倾注上层培养基这一方法的标准差最小, 最为稳定。测量审核样品|Z|＜2、空白样品为0 CFU/50 mL, 结果满意。结论 采用滤膜法倾注上层培养基的方法更适用于矿泉水中产气荚膜梭菌的检验, 并建议优先采用TSC培养基, 以确保检测结果的准确性和质量。

英文摘要:

      Objective To compare and analyze the effects of 4 methods on the measurement results of Clostridium perfringens in mineral water. Methods Based on the measurement audit work instruction, GB 8538-2016 National food safety standard-Test method for testing natural mineral water drinking and GB 4789.13-2012 National food safety standard-Microbiologyinspection-Clostridium perfringens test, the sulfite polymyxin sulfamethazine (SPS) agar and tryptose sulfite cycloserine (TSC) agar in 2 standards were used for culturing. And then the simultaneous detection of measurement audit samples and simulated water samples were carried out by the filter method of pouring the upper medium and the filter method of not pouring the upper medium. The recovery rates of Clostridium perfringens were compared between the 2 media, the analysis of variance was used to measure the measurement audit samples, and the paired t test was used to simulate the water samples, and then the impact of the 4 methods on the consistency of the counts of Clostridium perfringens in mineral water was evaluated. Results There was no significant difference in the test results of the 4 methods, but the target bacteria was difficult to appear black after being cultured without pouring the upper medium, and the target bacteria was black after being cultured by pouring the upper medium. The average recoveries of Clostridium perfringens from 3 manufacturers’ SPS media and TSC media were 89% and 98%. The standard deviation of the TSC medium and filter membrane method of pouring the upper medium was the smallest and the most stable. The measurement review results were |Z| <2 and 0 CFU/ 50 mL, and the results were satisfactory. Conclusion The method of pouring the upper medium by the filter method is more suitable for the detection of Clostridium perfringens in mineral water to ensure the accuracy and quality of the test results, and it is recommended to use TSC medium as the first choice.