Abstract: Packaging materials with good barrier properties can effectively extend the shelf life of meat. Chilled meat with modified atmosphere packaging (MAP) has different shelf lives because of the complexity of gas ratio and the diversity of packaging materials. In our present study, chilled pork was packaged under high-oxygen MAP (35% CO2 and 65% O2) using three materials with different levels of barrier property (high, medium and low) and determined for total bacterial count (TBC), coliform count, color, TVB-N, drip loss and pH during cold storage in order to observe the effect of packaging materials on the shelf life and quality of chilled pork. The results showed that the total plate count of meat packaged with high barrier material (PET/CPE film) after 10 days of storage exceeded food safety standards. The pH was at freshness grade 2 during storage. The TBC of meat packaged with medium barrier material (PE/PA film) did not exceed 6 lg(CFU/g) during the shelf life, the color was maintained well, the sensory quality was relatively better, but the drip loss was higher. Low barrier material (PA/CPP film) resulted in the biggest change in the TBC of chilled meat, which reached 6.46 lg(CFU/g) on the 13th d, and meanwhile the color, odor and overall acceptability were poor. Therefore, PE/PA film can provide a better barrier material for meat preservation under high-oxygen MAP.

Key words: chilled meat, packaging materials, modified atmosphere packaging