PLA-Based Films Reinforced with Cellulose Nanofibres from Salicornia ramosissima By-Product with Proof of Concept in High-Pressure Processing

Biocomposite films based on polylactic acid (PLA) reinforced with cellulose nanofibers (CNFs) extracted from Salicornia ramosissima by-products were developed and characterised using solvent casting (SC) and electrospinning (ES) techniques. The primary objective was to assess their suitability as sustainable food packaging materials that are compatible with high-pressure processing (HPP). The SC films exhibited a transparent, homogeneous morphology with superior ductility and water vapour barrier performance, whereas the ES films displayed a fibrous, porous structure with enhanced tensile strength and rigidity. The incorporation of CNFs significantly improved the mechanical properties, particularly the tensile strength and Young’s modulus, with optimal reinforcement achieved at a loading of 0.5%. Thermal and spectroscopic analyses confirmed the effective integration of CNF without compromising the thermal stability of PLA. Pouch-type packages from CNF-reinforced SC films withstood industrial HPP conditions without rupture or leakage, demonstrating their technical feasibility for food packaging applications. This study presents the first demonstration of Salicornia ramosissima by-product valorisation for CNF production and its application in HPP-compatible food packaging, addressing both circular economy goals and emerging food processing technologies.