在4个不同的加工工厂生产的单份液体牛奶的格兰氏阴性消化后污染模式
T T Lott1, A N Stelick1, M Wiedmann1
1Department of Food Science, Cornell University, Ithaca, NY 14853.
Journal of dairy science
|September 30, 2023
概括
单剂量牛奶由于格拉姆阴性细菌的污染而变坏得更快,这可能是由于不卫生的填充剂设计. 干预清洁纸板成型的干预措施并没有减少损坏,这表明设计缺陷.
科学领域:
- 食品微生物学 食品微生物学
- 乳制品科学 乳制品科学
- 食品安全 食品安全
背景情况:
- 历史数据表明,与半加容器相比,一次性牛奶在14天后的加工后具有更高的细菌数量和更低的感官得分.
- 过巴氏消极细菌对巴氏消极细菌的巴氏消极化后污染是可疑的原因,增加了单份牛奶的腐烂.
研究的目的:
- 综合评估一次性高温,短时间 (HTST) 流体牛奶的微生物质量和保质期.
- 为了确定一次性牛奶生产中格拉姆阴性污染的来源.
主要方法:
- 在两次访问期间,分析了来自四个商业设施的265个混合单次HTST液体牛奶样本.
- 微生物质量评估,包括格拉姆阴性细菌的破坏频率和细菌数量.
- 设施内调查和ATP抽样测试以确定污染源,重点关注制造纸箱的板.
主要成果:
- 格拉姆阴性腐败频率在各设施中从14%到79%不等,访问,设施,牛奶类型和填充车道之间存在显著差异.
- 带有格拉姆阴性污染的牛奶在第7天和第14天表现出更高的细菌数量和更低的感官得分.
- 像Pseudomonas和Bacillus这样的细菌属经常从牛奶样本和纸箱形成的囊中分离出来.
结论:
- 一次性填充剂的不卫生设计可能是造成格兰负污染的根本原因.
- 尽管有干预措施来改善纸箱成型的清洁,但毫克阴性腐败频率并没有显著降低.
- 对填充剂设计和卫生协议的进一步调查对于提高单次牛奶质量至关重要.
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