The Effect of Thyme (Zataria multiflora boiss) Essential Oil against Bacterial and Fungal strains in Mayonnaise

Essential oils are considered as alternative to synthetic preservatives in food products because of their antimicrobial properties. The aim of this study was to identify the main components of thyme (Zataria multiflora boiss) essential oil and to evaluate the antimicrobial activity of essential oil in vitro and mayonnaise. The essential oil was extracted by distillation and analyzed by gas chromatography. The antimicrobial activity of the essential oil was evaluated by determining the minimum inhibitory concentration and minimum bactericidal concentration. GC analysis of the essential oil resulted in the identification of forty compounds by a high number of monoterpenes such as thymol and carvacrol. The most susceptible pathogens were the fungi (lowest MIC) and the most resistant pathogen to Gram-negative bacteria. This study confirms that the essential oil of thyme possessed antimicrobial properties in vitro. In the second phase, efficiency of essential oil as natural preservative in high fat and low fat mayonnaise kept during storage at 4 oC for 6 months was studied. The results showed that of essential oil had influence against all of the tested microorganisms in mayonnaise and the pathogens did not grow in mayonnaise formulations, whereas in the control mayonnaise all of the pathogens and fungus grew. In conclusion the essential oil of thyme (Zataria multiflora boiss) would lead to control food pathogen and food spoilage organisms as natural food preservative and therefore, it would be used in biotechnological fields as natural preservative ingredients in food industry.