Ozone production by Dielectric Barrier Discharge Plasma for microbial inactvation in rice

Research on ozone production by using silent plasma or Dielectric Barrier Discharge Plasma (DBDP) and implemented for microbial inactivation in rice has been done. The plasma reactor for ozone generating were reactor with multi-point-plane (MP-P) reactor and spiral-cylender (S-C) reactor configurations. The high voltage AC has been used with voltage up to 40 kV and maximum frequency 23 kHz. For implementation in rice, this research used a Randomized Block Design (RBD) with 5 treatments and 4 replications in each treatment. Exposure time was varied such as: 0, 30, 60, 90, and 120 minutes. Total bacteria and molds (fungi) has been detected by using Total Plate Count (TPC) methods with nutrient broth as media for bacteria and, we found that MP-P Reactor needed less voltage comparing with S-C Reactor for the same cocentration ozone. Ozone generated by DBDP can reduce the population of bacteria and fungi in rice. The exposure for 90 minutes can eliminate 58.41% population of bacteria, and 26.23% population of fungi. Through analysis of variance known that ozone treatment is significantly affect the total bacteria at significance level of 5% and 1% (P <;0.05). However, treatment of fungi shown no significant effect, even at the 5% significance level (P> 0.05). Subtances of water, fat, and protein in rice was not change before and after ozone treatment.