INACTIVATION OF ESCHERICHIA COLI SUSPENDED IN LIQUID EGG USING PULSED ELECTRIC FIELDS

Abstract

Liquid egg inoculated with Escherichia coli was exposed to a 26kV/cm pulsed electric field with 2 and 4 μs pulse duration, 1.25 and 2.50 Hz pulsing rates, up to 100 pulses/unit volume, and stepwise and continuous recirculation treatment schemes while maintaining a bulk temperature below 37C. The inactivation of E. coli was a function of the pulse duration and the number of pulses. The destruction of Escherichia coli in liquid egg followed a first order kinetic and the treatment was more effective when the applied pulses were of a 4 μs pulse duration. A 6D reduction was obtained for viable E. coli using both pulsing rates and treatment schemes with no protein coagulation.