Antifungal activity of Thymus daenensis and Satureja hortensis essential oils (0, 50, 100, 150 ppm) were evaluated against Aspergillus fumigates in vitro and in the Food model system (un-heat and heat treated Doogh) during 21 days. In vitro results showed that minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of T. daenensis and S. hortensis oils were 6.25% and 12.5%, respectively. In un-heat treated samples, both EOs showed a significant inhibitory effects rather than the control group at 25 ºC than 4 ºC. Treatments containing 100 and 150 ppm of T. daenensis EO on the 21th day and treatment containing 50 ppm of S. hortensis EO on the 15th day had maximum inhibitory effect. No growth was observed in the heat treated samples and control group. The findings revealed that both EOs had noticeable antifungal activity and can be considered as a natural preservative in the food industry.
