The effect of oregano essential oil on survival/death of Salmonella typhimurium in meat stored at 5°C under aerobic, VP/MAP conditions

The effect of oregano essential oil and film permeability on the behaviour of Salmonella typhimurium in sterile and naturally contaminated beef fillets stored under aerobic, modified atmosphere consisting of 40% CO2 /30% O2 /30% N2 (MAP) and a vacuum packaged (VP) environment was studied during storage at 5°C. In samples without oregano essential oil, the pathogen survived under all storage conditions. Addition of oregano essential oil at a concentration of 0·8% v/w resulted in an initial reduction of 1–2 log10 cfu g−1 of the majority of the microbial population of meat with lactic acid bacteria and S. typhimurium showing the greatest reductions in all gaseous environments regardless of film permeability. The use of VP/MAP at chill temperatures in conjunction with oregano essential oil as a means of controlling spoilage and safety of meat is discussed.