Antimicrobial nanoemulsion formulation based on thyme (Thymus vulgaris) essential oil for UF labneh preservation

Abstract

The present study was evaluated and fabricated the thyme essential oil (TEO) nanoemulsion form to use in preservative of UF labneh. The antimicrobial and chemical composition of the oil was determined by well diffusion method and Gas chromatography–mass spectroscopy (GC–MS). The TEO nanoemulsion was characterized by Dynamic light scattering (DLS), Transmission electron microscope (SEM), and time killer effect. Inclusion TEO exhibited high inhibitory effects against numerous pathogenic strains, in which the diameter of inhibition ranged from 10 to 36 according to different concentrations of TEO. The GC–MS analysis of TEO has detected 15 compounds mainly thymol (43.63%). TEO nanoemulsion was almost spherical with a diameter of 52 nm and able to eliminate pathogenic counts within 60 min. The fortified labneh with different concentrations (0.1, 0.2, and 0.3%) TEO nanoemulsion was kept the quality of labneh up to six weeks. The counts of psychrotrophic, mold, and yeasts were indicated in the eighth week compared with control. The addition of TEO nanoemulsion was affected slightly on chemical properties during storage. Therefore, the highest total scores were given to labneh with 0.1% TEO nanoemulsion. The results suggested that the formulated TEO nanoemulsions might be a promising agent to prolong the shelf life and enhanced the aroma of labneh.