Deliverable 4.5 defines the methodological framework developed in WP4 of the R3PACK project to design, produce and upscale high-barrier fibre-based food packaging as alternatives to conventional plastics. The report structures the work around a dual strategy combining a long-term R&D path, focused on innovative recyclable, highly bio-based and even compostable multilayer fibre-based solutions (flexible, trays), and a short-term path aimed at rapidly deploying more mature paper-based packaging on existing industrial lines to highlight adjustments to settings and equipment. The long-term path successfully identified synergies, optimal combinations and order of barrier layers with a lot of different materials (MFC, CNC, PHBV, chitosan, inorganic) and functionalization technologies (additives, spray-coating, dispersion coating, thin layer vacuum deposition, lamination,…) providing mechanical strength, sealability and barrier properties for both flexible and tray formats. The most promising prototypes achieved more than 80% paper and from 90% to 100% bio-based content, being mainly recyclable and even home-compostable for the barrier cellulosic tray. Lab and pilot trials demonstrated competitive performance compared with conventional materials, while highlighting remaining challenges, e.g. coating uniformity, mechanical and thermal sensitivity, balance between recyclability and performance, and cost-performance of biobased coating formulations. The short-term path successfully validates that selected paper-based solutions can already meet technical requirements (machinability, shelf life) for certain product categories, particularly dry and semi-dry foods, with necessary adjustments to existing lines (sealing profile, pressure, temperature, etc.). Indeed, extensive machinability tests were carried out on paper reels in collaboration with Fraunhofer IVV (bending, friction, tension, seal strength), resulting in a best‑practice guidance document to support and helps food manufacturers of the programme to integrate fibre‑based packaging into their current production lines. Overall, the deliverable concludes that recyclable and high-barrier fibre-based food packaging is technically achievable for some products, while confirming that current fibre-based solutions are not yet competitive at scale. Higher material costs, reduced packaging speeds and remaining performance limitations continue to constrain short-term market uptake.
Boutin et al. (Wed,) studied this question.