Inactivation of Naturally Grown Microorganisms in Orange Juice Using Pulsed Electric Fields

In this paper, the effect of pulsed electric fields (PEFs) on naturally contaminated orange juice was investigated. A 2-log reduction in a colony count for the naturally grown microorganisms was achieved after application of 120 pulses/mL at a PEF level of 46 kV/cm. Also, the effect of the PEF on microorganisms inoculated in orange juice was studied. Compared to the naturally grown microorganisms, about 1-log more reduction was observed with inoculated microorganisms that were subjected to the same PEF conditions. The results suggest that other factors like the increased temperature and antimicrobial additives might be required to enhance the killing efficiency. A 20 degC increase in temperature prior to the application of the PEF resulted in about 1-log more reduction in microorganisms