Evaluating the effect of Commiphora Myrrha aqueous extract on the chemical and microbial properties of ground beef at refrigerator temperature

The myrrh herb by the scientific name of Commiphora myrrha is traditionally used for chronic diseases treatment, anti-inflammatory, painkiller, and an antimicrobial agent. The aim of the present study was to investigate the effect of aqueous extract on properties of ground beef stored at refrigerator temperature. In this study, aqueous extract (0.5, 2, and 3%) of Commiphora myrrha (Myrrh) was used as a Bio Preservative to extend the shelf life of the ground beef during 14 days of storage at 4 °C. In this study, chemical properties (peroxide value, Thiobarbituric acid value, and total volatile basic nitrogen), microbial properties (total count of microorganisms, Staphylococcus aureus, and psychrophilic and mesophilic bacteria), and sensory properties of ground beef samples were evaluated. Examination of pH changes showed that by increasing the storage time up to 7 days, the pH of all samples decreased (p<0.05), and then from 7 to 14 days, the pH of the samples increased significantly (p<0.05). Changes in oxidative indices, i.e. peroxide index and Thiobarbituric acid index, showed that increasing the storage time led to an increase in these indices, but the use of Myrrh extract prevented significant changes in oxidative indices (p<0.05). Measurement of the TVB-N index showed that by increasing storage time, this index increases, by increasing the level of bio preservatives significantly (p<0.05) led to a decrease in TVB-N changes. Examination of the antimicrobial activity of Myrrh extract in ground beef showed an increase in the total count, S. aureus, and psychrophilic and mesophilic bacteria in the tested samples. However, by increasing the concentration of Myrrh extract (p<0.05) significantly reduced the microbial population and minimized their changes. The sensory evaluation of ground beef samples showed that the treated sample with 3% Myrrh extract had the highest score and also the highest acceptability as compared to other samples. It might be concluded that the application of 3% Myrrh extract as a bio preservative to extend the shelf life of perishable products is a promising way to reduce the use of chemical preservatives in these products.