Decontamination of frozen cherries by innovative light-based technologies: Assessment of microbial inactivation and quality changes

Foodborne pathogen L. monocytogenes is a major concern in the frozen food industry. In this study, the decontamination efficiency of UV-C and HIPL for the inactivation of L. monocytogenes on frozen cherries was evaluated for the first time. Frozen cherries were exposed to light treatments at various light doses (3, 6, 9, 12 J/cm(2)) and lamp distances (10 and 20 cm). Moreover, samples were washed with/without chlorine solution (300 ppm) for 60 s as a commercial treatment. The highest reduction of L. innocua was observed as 2.90 log CFU/g by HIPL (9 J/ cm(2)-20 cm). The HIPL inactivation kinetic data of L. innocua were well described using the Log-Linear equation. D value (J/cm(2)) required to reduce the Listeria population by 90% was 5.42 J/cm(2) (at 10 cm). Unlike UV-C, the surface temperature of samples did not exceed 0 degrees C during HIPL at all parameters. The experiments show that HIPL treated cherries had statistically lower total anthocyanin and higher total phenolics than the untreated control.