PET trays coated with Citrus extract exhibit antioxidant activity with cooked turkey meat

A natural Citrus extract with potential antioxidant activity was evaluated as an ingredient for the production of active food packaging. The extract, in methanol, was sprayed onto the surface of polyethylene terephthalate (PET) trays. For comparison, a second set of trays were prepared using α-tocopherol as the coating. The effectiveness of the two types of packaging in delaying lipid oxidation in cooked turkey meat slices, stored at 4 °C over 4 days, was compared using 2-thiobarbituric acid-reactive substances (TBARS) and hexanal assays. TBARS and hexanal values, for meat stored on the Citrus extract coated trays, were significantly lower (P < 0.01) than those of meat stored on uncoated (control) trays while α-tocopherol coated trays exhibited no significant effect compared to control trays (P > 0.05). The effectiveness of the Citrus extract coating, compared to the α-tocopherol coating, was attributed to its higher surface roughness, demonstrated by optical profilometry, and the higher level of release (solubility) of the antioxidant in water.

► Active antioxidant packaging can be prepared by coating PET food trays with Citrus extract. ► PET trays coated with Citrus extract have a significant antioxidant effect on cooked meat in refrigerated storage. ► Compared to Citrus extract, α-tocopherol on PET is ineffective in inhibiting lipid oxidation. ► The antioxidant effect of Citrus coating may be due to its surface roughness and water solubility.