Effects of thermosonication on the fate of Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice

In this study, the effects of thermosonication and thermal treatment on Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice were investigated at 50 and 60 degrees C. Besides, nonlethal injury of Salm.Enteritidis after both treatments was also examined. The highest inactivation was attained with thermosonication at 60 degrees C. The inactivation rate was different for both pathogens, and Salm.Enteritidis was found to be more sensitive to thermosonication than E.coli O157:H7. Salmonella Enteritidis was recovered in all treated samples, except those subjected to more than 5-min thermosonication at 60 degrees C. It was found that the introduction of high-intensity ultrasound enhanced the inactivation of pathogens compared to thermal treatment alone. On the other hand, Salm.Enteritidis was detected in a number of samples following incubation in universal pre-enrichment broth, but no growth was detected after incubation in mango juice. Significance and Impact of the Study Fruit juices are commonly heat treated to inactivate micro-organisms and enzymes. However, excessive heat treatments may result in undesirable changes in juice quality. Treatment by power ultrasound, a nonthermal technology, may be an alternative processing technique to pasteurize fruit juices. This study highlights the effectiveness of thermosonication in inactivating Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice.