A comparison study on the antibacterial efficiency of essential oil and dried powder of Ocimum basilicum in ground beef during refrigerated storage

Basil known as Ocimum basilicum is one of the most popular aromatic herbs in daily diet to which several beneficial effects were attributed in herbal medicine. The aim of this study was firstly to compare the antibacterial activity of the essential oils of white and red varieties of basil in invitro condition and to choose the superior variety with higher antimicrobial potential. Secondly, a comparison of antimicrobial effect of the essential oil and the dried powder of the selected variety in microbial stability of ground beef during cold storage was come in to consideration. In the first step of the present research, antibacterial activity of essential oil of white and red basil varieties was evaluated by disk diffusion agar. In the second step, essential oil of white holy basil at 0.1% and also its dried powder (22%, correspond to the given amount of essential oil) were added to some fresh homogenized beef, the total counts of the treated samples as well as the control were monitored during the 10 days refrigeration. Essential oil of white basil showed superior antibacterial property than the red one; at the concentration level of 20mg/ml the difference in the inhibition zones was statistically different (0.05>P) while, relative differences could be seen at the two other tested concentrations (5 and 10 mg/ml). In the second step of the study it was shown that both applied treatments (essential oil at 0.1% and dried powder at 22%) can effectively retard microbial flora in beef during cold storage period. The results indicated that both essential oil and dried powder of Ocimum basilicum increased the microbial stability of ground meat during storage, whereas dried powder showed more preservative capability at final days of storage. So it is possible to use this kind of natural product instead of synthetic one to reduce the disease of consumers and enhancing the organoleptic features of food