Evaluation of the barrier properties of biobased and biodegradable PHBV cups for a usage benefice in cheese applications

Abstract

This study aims to characterize the barrier properties of polyhydroxyalkanoate cups (PHBV) or PHBV cups containing 20 % of cellulose fibers or 20 % of wood fibers in order to estimate the usage benefice in terms of food preservation to replace petrol-based packaging as polypropylene (PP), by bio-based and biodegradable PHBV packaging. For that, a previously developed model integrating (i) gases permeation through the lid film and the cup and (ii) sorption and diffusion of gases into the food (if any) was used. The O₂ and CO₂ permeabilities of PHBV were identified to 2.3 × 10⁻¹⁶ mol m⁻¹.s⁻¹.Pa⁻¹ and 4.5 × 10⁻¹⁶ mol m⁻¹.s⁻¹.Pa⁻¹ respectively at 23 °C, while the activation energy of these two parameters was estimated to 20.3 and 23.2 kJ mol⁻¹ respectively. The integration of fibers in the PHBV packaging increased the gases permeabilities by a factor 11 to 23 for O₂ and 5 to 10 for CO₂, due to the presence of factures and holes in the cups. Based on the permeability values identified and thanks to 2D numerical simulation, it was concluded that PHBV packaging cups seems promising to replace PP packaging for products under modified atmosphere, and more specifically could maintain a similar shelf life than commercial packaging did for MAP product with intermediate shelf life such as fresh cheese.