Impact of measures to increase packaging recyclability in stability of plant-based burgers: A comparative study between multilayer and monolayer lidding films

Abstract

Abstract

The expanding market of plant-based meat analogues (PBMA) drives innovation toward sustainable packaging systems that ensure both product safety and environmental performance. This study aims at investigating the impact of measures to increase packaging circularity on the shelf life of plant-based burgers under refrigerated, modified atmosphere conditions. Two packaging systems were compared: a conventional polyethylene terephthalate (PET)-based tray with multilayer lidding system (STD) and a tray with a recyclable lidding film consisting of a machine-direction oriented polyethylene (MDO PE) monomaterial (NEW). Physicochemical (moisture, pH, titratable acidity, total volatile basic nitrogen, peroxide value, colour, texture, volatiles, and headspace gas composition), microbiological (total viable count, lactic acid bacteria, yeast and moulds, pathogens, and 16S rRNA sequencing), and sensory parameters were monitored during storage for 23 days at 4 ± 2 °C. Packaging materials were characterised for gas barrier and environmental impact. Results showed a similar performance for microbial growth at the end of shelf life in both packages. The NEW packaging showed to protect slightly less against oxidation and protein degradation. Sensory evaluation revealed more complex odour attributes in STD over time, and a greater tendency towards degradation odours in NEW. However, the environmental impact analysis demonstrated that the NEW system presents a 25% lower impact in global warming potential than the STD. Overall, although there are some differences noted in the burger behaviour when packaged in the NEW packaging compared to the STD, results support that the change into the monolayer lid can be performed, favouring circularity without relevant prejudice of the burger preservation. The findings inform sustainable packaging design for PBMA, highlighting the trade-offs between product stability and environmental performance in monomaterial versus multilayer systems. Results support packaging circularity strategies and European Packaging and Packaging Waste Regulation alignment for plastic packaging.