Synergistic Effects of Combined Disinfection Using Sanitizers and UV to Reduce the Levels of Staphylococcus aureus in Oyster Mushrooms

Synergistic effects of combined treatment of sanitizers, including ethanol, hydrogen peroxide (H₂O₂), sodium hypochlorite (NaOCl), and UV radiation on eliminating Staphylococcus aureus ATCC 35556 found in oyster mushrooms were evaluated. Various concentrations of ethanol (10, 30, 50, and 70%), H₂O₂ (100, 500, 1000, 1500, and 2000 ppm) and NaOCl (20, 60, 100, 150, and 200 ppm) were tested along with various UV exposure doses (6, 96, 216, 360, and 504 mWs/㎠). The combined sanitizers/UV treatments produced greater reductions in bacterial counts than either treatment alone. The synergistic values of combined ethanol/UV, H₂O₂/UV, and NaOCl/UV treatment with regards to the elimination of S. aureus were 0.93-2.35, 0.07-0.93, and 0.06-0.89 log∧10 colony forming unit (CFU)/g, respectively. These results suggest that the significant synergistic benefit in eliminating food-borne pathogens on oyster mushroom results from combined sanitizer/UV treatment.