Impact of Recyclable Packaging on Microwave-Treated Chicken Quality: A Comparison of PET vs PP with Modified Atmosphere

Abstract

This study evaluated the effectiveness of combining recyclable packaging materials in preserving the quality of microwave-treated chicken meat. Specifically, it assessed the combination of polyethylene terephthalate (PET) and polypropylene (PP) with modified atmosphere packaging (100% N₂ and 60% CO₂:40% N₂). Quality parameters, such as cook loss, color, microbiological stability, and sensory analysis, were monitored over 36 days. Gas composition, oxygen transmission rate (OTR), and thermal properties were also examined. Results indicated that after heat treatment, no statistically significant differences were observed among the packaging materials in terms of cook loss, color, and microbiological shelf-life. However, the PP trays exhibited a higher OTR than PET trays after heat treatment and contact with the chicken. While heat treatment did not affect the thermal properties of either tray, the PP trays showed a shift in crystallization and melting temperature after 28 days of food contact, indicating changes in material properties over time. Sensory analysis revealed lower acceptance scores and more negative sensory attributes for samples in PET trays, possibly due to the suitability and sealing properties of the films for heat treatment. These findings suggest that while microwave treatment effectively extends the microbial shelf life for chicken, the choice of packaging material and gas composition may influence other aspects through storage, such as sensory perception and material integrity.

Keywords: Microwave heating; Modified atmosphere packaging; Quality; Recyclable packaging; Shelf life; Thermal processing.