Microbial inactivation by ultrasound for enhanced food safety

Inactivation of foodborne pathogens by power ultrasound provides an alternative to traditional thermal processing modalities with potential for minimizing food-quality degradation. To enhance the efficacy of an ultrasonic treatment, it is often combined with other physical or chemical lethal factors which help to shorten the treatment time and improve quality retention. The inactivation mechanisms, thermodynamic aspects, and kinetic modeling of ultrasonic microbial inactivation will be discussed. The critical issue of how to achieve a relatively uniform acoustic field distribution in a treatment chamber will be investigated by computer simulation and verified with microbial inactivation tests. Inactivation of foodborne pathogens in liquid foods and surface decontamination of fresh produce and nuts will be used as examples to show the potential of ultrasound-assisted processes. Lastly, the effect of sonication on the quality of the treated food products will be examined.