Shelf Life Determination of Fresh Cheese Subjected to Different Modified Atmospheres Packaging

The aim of this study was to determine the physicochemical, microbiological, and sensory properties as well as shelf life of fresh mozzarella cheese samples. Fresh mozzarella cheese samples were packaged under five different Modified Atmospheres (MAP): Vacuum (Atm 2), 40% CO2/ 60% N-2 (Atm 3), 60% CO2/ 40% N-2 (Atm 4), 100% CO2 (Atm 5) and 100% N-2 (Atm 6). Identical cheese samples were packaged in air (Atm 1), taken as the control. All cheese samples were kept under refrigeration (4 +/- 1 degrees C) for 6 weeks. Atm 5 gas mixture was the most effective for inhibiting aerobic microflora growth in cheese samples stored at 4 degrees C during 6 weeks. Lactic acid bacteria were not affected by CO2 presence even in high concentrations. Yeasts and moulds were totally inhibited by Atm 5 gas mixture throughout the entire storage period. Sensory evaluation showed that cheese packaged under Atm 3 retained good sensory characteristics for 6 weeks of storage while control samples were appreciated the least. Atm 5 provided the best shelf life extension at 4 degrees C by 81 days, compared to the control.