Anti-Listerial Activity of Oregano and Cinnamon Essential Oils in Vacuum Packed Ground Ovine Meat during Refrigerated Storage

This work aimed to study the antibacterial activity of various Essential Oils (EOs) against food borne pathogens as well as the effect of their incorporation at different concentrations on vacuum-packed ground ovine meat, experimentally inoculated with Listeria monocytogenes, during 12 days of storage at 4°C. In summary, pathogenic bacteria, particularly L. monocytogenes, Salmonella enteritidis and Escherichia coli, showed high sensitivity towards citrus, rosemary, thyme, cinnamon and oregano EOs due to their richness in bioactive compounds. The Minimum Inhibitory Concentrations (MICs) of various EOs against L. monocytogenes and E. coli were about 0.5% for oregano and thymus EOs and 0.7% for cinnamon EO. Besides, addition of EOs at different concentrations resulted in the improvement of biochemical and microbiological qualities of ground vacuum packed sheep meat, during refrigerated storage. High concentrations of oregano (1%) and cinnamon (1.4%) EOs had the most efficient antilisterial activities compared to the control and other meat samples. The treatment of ovine meat with oregano or cinnamon EOs preserved a better content of proteins, a high ratio of PUFAs and a favorable balance between w-6 and w-3 PUFA, resulting in the production of healthier meat.