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Various physical properties of vacuum packaging and wrap films used for packaging chilled meat were investigated. Polyvinylidende chloride coextruded between ethylene vinyl acetate (PVDC/EVA) shrink films showed generally lower water vapor transmission rate (WVTR) and oxygen transmission rate (OTR), but higher tensile strength, than polyamide laminated to polyethylene (PA/PE) films. When the PVDC/EVA films shrank unrestrained without contents, the shrink rates ranged from 34.9 to 48.5% in machine direction and from 40.9 to 57.3% in transverse direction, respectively. Furthermore, thickness was increased by about two- to threefold, resulting in decrease of tensile strength, OTR and WVTR. The thickness of polyvinyl chloride (PVC) wrap films was in the range of 11 to 13 ㎛, whereas that of linear low density polyethylene (LLDPE) films was 9 to 12 ㎛. The average WVTR of PVC wrap films was considerably higher than that of LLDPE films. PVC wrap films had lower haze values than LLDPE films. Most wrap packaging materials except two LLDPE samples had OTR values over 20,000 ㎤. Although physical properties of wrap films varied depending on the manufacturers, all materials tested were acceptable for packaging fresh chilled meat.
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