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增长和非热性无活化
Anna Austrich-Comas1, Cristina Serra-Castelló1, Maria Viella1
1Food Safety and Functionality Program, IRTA, Finca Camps i Armet, E-17121 Monells, Spain.
Foods (Basel, Switzerland)
|June 10, 2023
概括
干燥固化火腿 (DCH) 中金黄色葡萄球菌的生长取决于水的活动,包装和温度. 模型预测病原体的行为,有助于对货架稳定的DCH的风险管理.
科学领域:
- 食品微生物学 食品微生物学
- 食品安全 食品安全
- 预测建模预测建模
背景情况:
- 干燥固化火腿 (DCH) 支持金色葡萄球菌的生长,因为它具有耐性.
- 病原体的生长可能会损害DCH的保质性,需要进行风险评估.
研究的目的:
- 在各种条件下,在切片的DCH中评估金黄色葡萄球菌的行为.
- 开发DCH中S. aureus生长和无活化的预测模型.
主要方法:
- 在空气,真空或MAP包装下,在2-25°C下,在DCH (aw 0.861-0.925) 中评估金黄色菌的行为,长达1年.
- 逻辑和韦布尔模型适用于初级动力学;多项式模型适用于二级动力学.
- 为每个包装类型开发的全球模型.
主要成果:
- 在空气包装下,S. aureus在20-25°C的高度DCH中生长.
- 在较低的aw时观察到无活化,在15°C时在空气包装的DCH.中更快.
- 真空和MAP包装在更高的温度下显示出更快的无活化,独立于 aw.
结论:
- 在DCH中S. aureus的行为受到储存温度,包装和水活动的显著影响.
- 开发的模型提供了一个用于DCH风险管理和防止S. aureus发展的工具.
- 基于 aw 和储存温度的最佳包装选择对于货架稳定性至关重要.
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