Modeling of Inactivation of Zygosaccharomyces rouxii in Apple Juice by Surface Discharge Plasma

Abstract

Objective: Establish a computer model for predicting the inactivation of Zygosaccharomyces rouxii in apple juice by surface discharge plasma (SDP). Methods: The numerical simulation software COMSOL multiphysics was used to model SDP inactivation of Z. rouxii LB. The inactivation efficiency was evaluated under different conditions of discharge voltage, bubble size and sample volume. The model was then validated. Results: SDP was highly effective in deactivating hyperosmotic-resistant yeast in apple juice. The reaction rate coefficient decreased with an increase in the initial concentration of bacteria. Furthermore, the increase in discharge voltage shortened the time needed to inactivate yeasts. Bubble size variations had no significant effect on the inactivation of Z. rouxii LB, and the inactivation time was prolonged with increasing sample volume. The model simulation results agreed with the experimental data.

Keywords

• surface discharge plasma; osmophilic yeast; inactivation; apple juice; model