脉冲电场预处理对山羊牛奶消毒的影响
Alberta Araújo1,2, Carla Barbosa1,3, Manuel Rui Alves1
1CISAS, Escola Superior de Tecnologia e Gestão, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial de Nun'Álvares, 4900-347 Viana do Castelo, Portugal.
Foods (Basel, Switzerland)
|November 14, 2023
概括
脉冲电场 (PEF) 与温和的热量相结合,有效地减少了山羊奶中的微生物,为传统消毒提供了节能替代品. 这种方法增强了微生物无活化,同时可能使能源消耗降低50%以上.
科学领域:
- 食品科学 食品科学 食品科学
- 微生物学 微生物学
- 工艺工程的过程工程.
背景情况:
- 羊奶的营养价值很高,但其热不稳定性给加工带来了挑战.
- 传统的热处理 (消毒,UHT) 确保了安全性,但可能会影响牛奶的质量.
- 像脉冲电场 (PEFs) 这样的非热方法为微生物减少提供了替代方案.
研究的目的:
- 评估将PEF与山羊奶的温和热处理相结合的有效性和能源效率.
- 评估PEF预处理对山羊奶中特定细菌的耐热性的影响.
- 为了比较PEF与热处理相结合的微生物失活效应与仅热处理的微生物失活效应.
主要方法:
- 羊奶被人工接种了Listeria monocytogenes和大肠杆菌.
- 作为预处理,应用了低强度的PEF (50 μs脉冲,3 Hz,10 kV·cm-1).
- 结合PEF和热处理 (例如63°C) 与仅热处理 (例如72°C) 的方法进行了比较.
- 分析了微生物减少,z值和能源消耗.
主要成果:
- 结合PEF和63°C热处理,实现了与72°C热处理单独相似的Listeria monocytogenes减少.
- PEF 预处理显著增加了 L. monocytogenes 的 z 值,表明诱导耐热性.
- PEF对大肠杆菌的活力产生了更明显的影响.
- 当使用PEF作为预处理时,热处理的能源需求减少了至少50%.
结论:
- 将PEF与中度热处理相结合,是羊奶安全性的有效和节能战略.
- PEF 预处理可能会改变细菌的耐热性,需要进一步调查.
- 这种方法为山羊奶的传统高温加工提供了一个有希望的替代方案.
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