干燥和测试:注射方法对低湿度食物持续性细菌群的影响
Manita Adhikari1, Kavita Patil1, Jennifer C Acuff1
1Department of Food Science, University of Arkansas System Division of Agriculture Fayetteville Arkansas USA.
Journal of food protection
|January 29, 2025
概括
研究人员开发了一种新方法,以创建现实的低湿度食物持久细菌群 (LMF PBPs) 来研究病原体生存. 在这些模型中,草基培养和特定的食物矩阵,如二氧化,改善了萨尔摩内拉田纳西州的生存率.
科学领域:
- 食品安全与微生物学
- 在食品加工环境中的细菌持久性
背景情况:
- 低湿度食品 (LMF) 加工中的病原体污染是一个重大的公共卫生问题,导致疫情和召回.
- 现有的实验室方法不足以模仿现实世界的污染和LMF环境中的藏,阻碍了有效的卫生战略的开发.
研究的目的:
- 为了比较不同的接种方法,以创建准确反映环境条件的低湿度食品持久细菌群 (LMF PBPs).
- 评估培养制备技术和食品矩阵对这些已建立的LMF PBP中的萨尔摩尼拉田纳西菌的生存的影响.
主要方法:
- 使用0.5毫升培养物和0.4克无脂干牛奶 (NFDM) 的泥方法在一致性和易用性方面得到了优化.
- 田纳西州的沙门氏菌使用草和制方法进行培养,并纳入各种食品矩阵 (NFDM,花生粉,粉,二氧化).
- 在受控条件下 (22-25°C,50%的RH) 储存了注射不钢优惠券,并在7天内计算了细菌种群.
主要成果:
- 草基培养产生的初始沙门氏菌田纳西州种群显著更高 (10.1日志CFU/cm2) 与基培养 (8.2日志CFU/cm2) 相比.
- 在所有矩阵中,草培养的细菌减少率比培养的细菌减少率低 (0.3-2.7 log CFU/cm2) (1.0-5.1 log CFU/cm2).
- 与其他食品矩阵或没有矩阵相比,二氧化 (SiO2) 矩阵中的沙门氏菌显著减少 (2.7-5.1 log CFU/cm2).
结论:
- 使用草培养的优化泥方法为研究LMF环境中的沙门氏菌持久性提供了更现实的模型.
- 培养方法和食物矩阵成分显著影响细菌的存活,突出了对特定环境的卫生研究的需要.
- 二氧化表明,由于增强的细菌减少,在LMF环境中研究病原体失活的矩阵具有潜力.
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