Decontamination of foodborne pathogens by different methods during blanching process of frozen french fries

The objective of this research was to study the decontamination of foodborne pathogens by different methods in blanching process water of frozen french fries potatoes. Efficiency of commercial liquid herbal extracts and thermosonication, which is an alternative method to conventional thermal treatment, for the bacteria such as Salmonella Typhimurium, Listeria monocytogenes and Escherichia coli O157:H7 were evaluated. In this study, thermal treatment and thermosonication were investigated at 40°, 50°, 60°C for 15 minutes, respectively. And in addition, the effect of commercial liquid herbal extracts were investigated at 25, 40, 50, 60°C for 1 minute. Thermosonication was effective on inactivation of foodborne pathogens at 40°C, at which thermal teratment showed no microbial inactivation effect when used alone. Thermosonication was reduced treatment time when compared with conventional thermal treatment at 60°C, at which thermal treatment alone is effective on inactivation of bacteria when used for enough time. Liquid herbal extracts treatment showed 2-8 log cfu/ mL reduction of foodborne pathogens at 40°C and 50°C in 1 minute. When heat treatment was 60°C liquid herbal extracts inactivated all foodborne pathogens. Accordingly, it is observed that treatment of liquid herbal extracts is effective on both inactivation of foodborne pathogens and reduction treatment time.