فهرست نشریات علمی دسترسی آزاد ایران

Introduction: Diseases caused by the consumption of bacteria-contaminated foods have been of great importance in public health. Therefore, control of dairy product contamination with coliforms is a concern for the durability of dairy producers. Control of the contamination by natural products may have dual action; nutritive value and natural antibiotics. In this study, the antimicrobial activity of thyme essential oil against Escherichia coli O157: H7 in doogh (Iranian fermented dairy drink) was examined and the MIC and MBC were determined. Methods: Antimicrobial activity of thyme essential oil was examined using different concentrations (0, 30, 60, 90, and 120 μl/ml) against bacteria with a density of 105CFU/ml during the 60-day at 4 °C. Moreover, the effect of different concentrations of essential oils on the taste of doogh was also studied. Taste evaluation was performed based on 5 points hedonic test to evaluate the effect of Thyme oil on the sense of taste. Duncan software was used to determine the difference between test and control groups at a confidence level of 5%. The SPSS software was also used for statistical analysis. Results: All concentrations of thyme essential oil could stop the growth of bacteria (P<0.05). The inhibitory effect of oil increased with increasing concentration and time. Based on the results of sensory (taste) evaluation, treatment 2 (containing 60 μl/ml of essential oil of thyme) was selected as the best treatment. Conclusion: Thyme essential oil can be used as a natural preservative with a positive impact on taste and nutritive value.