The crisp head lettuce (Lactuca sativa L.)was minimally processed, with the leaves being detached and cleaned, packaged in plastic bags made of polyethylene with modified atmosphere inside the bag. Two different atmospheres were applied: 10 and 15% of CO2, with the O2 level being reduced in both cases to 5%. After the packing, the lettuce was immediately refrigerated. The product quality with and without modified atmosphere was compared during the storage time. It was accompanied the changes in O2 and CO2 concentration inside the packaging and the product shelf life, through sensorial and microbiological analysis, and soluble solids variation. The influence of modified atmosphere in microorganisms grown and in soluble solids variation was not relevant. However this technology reduced the lettuce respiration rates and the quality sensorial loss during storage. The shelf life of lettuce in modified atmosphere was extended in five days in comparison with the ones packaged in normal atmosphere.
lettuce; minimally process; conservation; modified atmosphere