Microbial inactivation in fresh and minimally processed foods by intense pulsed light (IPL) treatment

The purposes of this study were to evaluate the inactivation effects of intense pulsed light (IPL) on indigenous and inoculated microorganisms in fresh and minimally processed foods and the industrial applicability of this nonthermal sterilization method. The samples were treated with IPL by varying the treatment time and voltage. The inactivation effect tended to increase as the treatment conditions increased. Further, indigenous microorganisms showed a lower inactivation level than inoculated microorganisms, E. coli ATCC 25922, due to the variability of indigenous microorganisms and their properties. Chopped garlic showed a higher E. coli inactivation effect (2.65 log reduction after 0.185 J/cm² of IPL) than peeled garlic (1.21 log reduction) due to its larger surface area. The manila clam showed a lower E. coli inactivation (0.93 log reduction) effect than squid (1.84 log reduction) due to its rougher surface. After the IPL treatment, there was no significant difference in temperature, moisture content, and color.