Pulsed electric field inactivation of diarrhoeagenic Bacillus cereus through irreversible electroporation.

Abstract

The physical effects of high‐intensity pulsed electric fields (PEF) on the inactivation of diarrhoeagenic Bacillus cereus cells suspended in 0·1% peptone water were examined by transmission electron microscopy (TEM). The levels of PEF‐induced microbial cell death were determined by enumeration on tryptone soy yeast extract agar and Bacillus cereus‐selective agar plates. Following exposure to lethal levels of PEF, TEM investigation revealed irreversible cell membrane rupture at a number of locations, with the apparent leakage of intracellular contents. This study provides a clearer understanding of the mechanism of PEF‐induced cellular damage, information that is essential for the further optimization of this emerging food‐processing technology.