This study aimed to gain more in-depth knowledge of the mechanisms involved in microbial inactivation by pulsed electric fields (PEF) to understand the tailing observed in survival curves of Salmonella Typhimurium (STCC 878). The comparison of the inactivation achieved by the application of one train of pulses with those obtained with pulses applied in two trains shows that the tail of the survival curves was a consequence of a transient increment of the microbial resistance to the effect of the electric field in a proportion of the cells. After some time following the application of the first pulse train, cells became again sensitive to the second train, and tailing tended to disappear. The required time was highly dependent on the characteristics of the incubation medium. Similar effects were observed when the treatments were validated on whole milk and orange juice. This study has demonstrated by the first time on microbial cells the benefits of splitting the delivered PEF treatment in two trains with a period of delay between them. Therefore, this insight opens up the possibility of developing new strategies to achieve the required inactivation levels to guarantee food safety by moderate PEF treatments.

这项研究旨在更深入地了解脉冲电场（PEF）灭活微生物所涉及的机制，以了解沙门氏菌存活曲线中观察到的拖尾现象。鼠伤寒（STCC 878）。通过施加一列脉冲与通过施加两列脉冲获得的灭活作用的比较表明，存活曲线的尾部是微生物抵抗电场电场的瞬时增加的结果。一定比例的细胞。在施加第一个脉冲序列后的一段时间后，细胞再次对第二个序列变得敏感，并且拖尾趋于消失。所需时间高度依赖于培养介质的特性。当对全脂牛奶和橙汁进行验证后，观察到类似的效果。这项研究首次在微生物细胞上证明了将已交付的PEF处理分成两列的好处，它们之间有一定的延迟。