Reduction of Listeria monocytogenes in Mozzarella Natural Cheese by Floating Electrode–Dielectric Barrier Discharge (FE-DBD) Plasma Treatment

Listeria monocytogenes is one of the major foodborne pathogens and is commonly detected in dairy products such as natural mozzarella cheese. In this study, the effects of FE-DBD plasma (1.1 kV, 43 kHz, N₂ 1.5 m/s, 5–90 min) on the microbial reduction of L. monocytogenes inoculated on natural mozzarella cheese and on pH changes were investigated. When FE-DBD plasma was applied for 5, 10, 30, 60, and 90 minutes, L. monocytogenes was reduced by 0.56, 0.69, 0.93, 1.50, and 1.97 log CFU/g, respectively. According to the Weibull model, the coefficient of determination (R²) was 0.98, and the D-value was calculated to be 25 min. For quality evaluation, pH analysis showed no significant difference between the control and treatment groups (p > 0.05). These results suggest that FE-DBD plasma treatment can enhance the safety of natural mozzarella cheese and protect the product from microbial hazards.