대기압 플라즈마 처리에 의한 쥐치포 중 주요 식중독세균의 살균 효과

Abstract

This study investigated the antibacterial effects of BioZone atmospheric plasma (AP) against Bacillus cereus (F4810/72) and Staphylococcus aureus (ATCC 6538) as the major foodborne bacteria on the surface of dried filefish (Stephanolepis cirrhifer) fillets. The fillets were experimentally contaminated with 7-8 log CFU/mL of B. cereus or S. aureus using a spot inoculation method. Bacterial counts were measured by standard plate method on tryptic soy agar, and were significantly reduced with the increase in the treatment time (1, 3, 5 or 20 min) of AP on the fillets (p < 0.05). The reductions of the pathogens by AP treatment ranged from 0.9 to 2.93 logCFU/g for B. cereus and from 1.04 to 2.55 logCFU/g for S. aureus. A reduction of >1-logCFU/g for B. cereus and S. aureus was observed on the fillets treated with AP for >3 min. The differences in color on the Hunter scale (L=light vs. dark, a=red vs. green, b=yellow vs. blue) of the fillets were not significantly different between the nontreated (control) and AP-treated fillets (p>0.05). This study suggested that 3 min of AP could be effective in reducing >90% of the bacteria without causing any concomitant changes in the color of the fillets.