Feasibility of Recycled Polypropylene for Reusable Food Packaging: Effects of Reuse Conditions on Packaging Performance, Material Properties, and Microbial Safety

ABSTRACT Reusable packaging is a promising solution to reduce plastic waste and mitigate the negative environmental impact of single‐use plastics. Furthermore, incorporating recycled materials can further enhance sustainability by reintroducing end‐of‐life plastic waste into a circular system. Although repeated use conditions, such as microwave heating and dishwashing, have been shown to result in alterations in the material properties of packaging, limited research exists on how reuse may impact recycled grades. It remains unclear whether recycled materials are more susceptible to degradation due to the treatment conditions involved in their refurbishment. This study investigates the feasibility of using postindustrial recycled polypropylene (PIR PP) as an alternative to virgin PP in reusable food packaging, with a focus on functionality, material properties, and microbial safety. Virgin PP homopolymer, virgin PP copolymer, and PIR PP were subjected to a simulated reuse protocol involving oven heating and dishwashing for up to 20 cycles. Material characterization and microbiological testing revealed no loss of performance or compromise of microbial safety in any of the three materials. The findings suggest that PIR PP performs comparably to virgin PP under repeated use conditions, supporting its suitability for reusable packaging and contributing to the development of circular and sustainable packaging solutions.