BACKGROUND: Cheese is recognized as a source of foodborne illness worldwide.OBJECTIVES: In this study, the growth inhibition of Aspergillus flavus inoculated on Iranian white cheese was investigated using cold atmospheric plasma and Zataria multiflora essential oil individually and in combination along with their effect on the sensory properties of cheese .METHODS: Slices of cheese cut in the presence and absence of 100 ppm of Zataria multiflora essential oil were exposed to cold atmospheric plasma for 2 and 5 minutes and stored in a refrigerator for 60 days. Afterwards, they were incubated in 5 time intervals (days 0, 15, 30, 45 and 60) and each was evaluated over a period of 10 days at 25 °C.RESULTS: Based on the results, the plasma inhibitory effect had a pattern dependent on the plasma flow time and the increase in the flow time reduced the radial growth rate of mold. At all times of plasma flow, a significant inhibitory effect was observed on the mold growth compared to the control group (P<0.05). In terms of growth inhibition percentage, the lowest inhibition was detected in the presence of essential oil alone and the highest inhibitory property resulted from 5 minutes of plasma flow with essential oil. There was no difference between the sensory properties of plasma-treated cheese and the essential oil in combination with those of plasma-treated samples alone. The findings also showed that the addition of essential oil had no effect on the sensory properties of cheese.CONCLUSIONS: Gliding arc plasma has inhibitory effects on the growth of Aspergillus flavus mold in cheese without adverse sensory changes, but the conditions must be optimized for industrial applications.

BACKGROUND: The hazardous nature of aflatoxins to human and animals necessitate the establishment of control measures. ObjectiveS: The effect of two medicinal plants, Satureja khozistanica and Satureja macrosiphon, was studied on inhibiting Aspergillus flavus growth and reducing aflatoxin B1-content in the liquid medium. Methods: Essential oils were isolated by hydrodistillation method, using a Clevenger-type apparatus. Various extracts of plant materials were macerated with various extraction solvents (ethanol, ethanol70% and water extracts). Essential oils (0, 62/5, 125, 250, 375 and 500 mg/l) and various extracts (0, 500, 1000, 2000, 4000 and 6000 mg/l) of S. khozistanica and S. macrosiphon were examined for reducing A. flavus growth and it’s AFB1-content in the liquid medium. Amount of aflatoxinB1 was evaluated by high performance thin layer chromatographymethod. Results: Essential oil of S. khozistanica at the concentration of 375 mg/l as well as its ethanol and ethanol 70% extracts at 4000 and 6000 mg/l  respectively caused complete inhibition of fungus mycelial growth, whereas essential oil and extracts of S. macrosiphon couldn’t inhibit Aspergillus growth completely even at the maximum concentration. Essential oils of S. khozistanica and S. macrosiphonia at the concentration of 250 mg/l reduced AFB1-production 98 and 33.52% respectively. Various Extracts of S. khozistanica exhibited stronger anti-AFB1-biosyntesis activity than those of S. macrosiphon, so that, ethanol, ehanol70% and aqueous extracts of S. khozistanica at 4000 mg/l reduced 100, 96 and 32.37% of AFB1-production, respectively. On the contrary, essential oils, ethanol and ehanol70% extracts of both plants couldn’t significantly degrade AFB1-contamination, whereas aqueous extractsof S. khozistanica and S. macrosiphonia at the concentration of 4000 mg/l resulted in degradation of 25 and 32.16% AFB1-content, respectively. ConclusionS: In general, Essential oil and ethanol extract of S. khozistanica considerably inhibited A. flavus growth as well as AFB1-biosynthesis while aqueous extract of S. macrosiphon showed strong AFB1-degradation activity.