在温度滥用条件下,黄金葡萄球菌的预测生长模型
Vijay K Juneja1, Marangeli Osoria1, Harsimran Kaur Kapoor2
1U.S. Department of Agriculture-Agricultural Research Service, Wyndmoor, PA, USA.
Food research international (Ottawa, Ont.)
|March 9, 2025
概括
为了评估食品安全风险,开发了黄金葡萄球菌 (S. aureus) 增长的预测模型. 这个模型准确地预测了温度滥用条件下的细菌生长,这对于预防食物中毒至关重要.
科学领域:
- 食品安全微生物学 食品安全微生物学
- 预测建模的预测建模.
- 细菌生长动力学 细菌生长动力学
背景情况:
- 黄金葡萄球菌 (Staphylococcus aureus) 食物中毒通常是由于食物处理和储存温度不当导致的.
- 预测模型是评估食品中的微生物风险的重要工具.
研究的目的:
- 开发和验证一个预测模型,用于金黄色葡萄球菌的生长动力学.
- 为了估计S. aureus在与食品储存相关的动态温度条件下的生长.
主要方法:
- 黄金菌的生长动力学数据在Tryptic大豆中收集,范围跨越同热温度 (748.9°C).
- 巴拉尼主要模型和拉特科夫斯基次要模型与增长数据相匹配.
- 使用第四阶Runge-Kutta方法开发了一个动态模型,以模拟温度波动下的细菌生长.
主要成果:
- 主要和次要模型都显示出与异热增长数据 (高R2,低RMSE/SSE) 的良好匹配.
- 该模型确定了S. aureus.的最小 (5.7°C) 和最大 (47.3°C) 的生长温度.
- 使用动态温度配置文件的验证显示,在可接受的预测区域内 (-1.0到0.5 log10 CFU/mL) 观察到的增长>70%.
结论:
- 开发的预测模型准确地估计了Staphylococcus aureus在各种温度条件下的生长,包括温度滥用.
- 该模型可以成为食品安全评估和风险管理策略的宝贵工具.
- 对S. aureus生长动态的更好理解有助于预防食物传播疾病.
相关概念视频
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01:23Microbial Growth Measurement: Direct Methods
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01:27Microbial Growth Measurement: Indirect Methods
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01:27Factors Influencing Microbial Growth: Temperature
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01:23Physical Methods for Controlling Microbial Growth: Temperature
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01:26Exponential Equations for Modeling Growth
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