Air bubble in liquid food under pulsed electric field pasteurization using coaxial chamber

Abstract

Dielectric breakdown of air bubbles embedded in liquid food is a limiting factor in the pulsed electric field (PEF) pasteurization. Therefore, a proper chamber's geometry, air degasification, and estimation of electric field enhancements (due to gas bubbles) are powerful strategies to overcome this limitation. In this study, a coaxial treatment geometry loaded by an orange liquid sample encompassing a gas bubble demonstrated importance in the electric field distributions. The development of a gas bubble induces the non-uniform electric field near the bubble surface. A numerical analysis through COMSOL Multiphysics was done to observe the effects of a bubble diameter and the liquid's flow inside the coaxial chamber geometry. An air bubble with a comparable diameter has influenced more to the electric potential difference, and the position of the air bubble also affects the value of perturbation in the electric potential. This study supports the development of an electroporator for PEF pasteurization of liquid food.