DESIGNING PEA PROTEIN-BASED PACKAGING MATERIALS WITH LIPOPHILIC NATURE USING POMEGRANATE AND SOUR CHERRY SEED OILS

Abstract

This study presents a new method to meet the increasing need for sustainable and bioactive food packaging by creating biocomposite films. These films are made by emulsifying 3% (v/w) cold-pressed pomegranate seed oil (PSO) and sour cherry seed oil (SCSO) into a hydrophilic pea protein matrix. The resulting active packaging materials, referred to as PSOF and SCSOF, were thoroughly compared with a control film made of oil-free pea protein (PPF). Adding these hydrophobic lipids notably increased the matrix's thickness from 0.05 to 0.11 mm and also decreased its moisture content from 23.42% to 12.61%. The distribution of oil droplets caused significant light scattering, raising opacity (1.88-2.45) and lowering surface lightness (L*: 86.57 to 76.33), indicating improved photoprotection. Mechanically, the active lipids acted as plasticizers. While tensile strength (TS) (8.05 to 5.10 MPa) decreased, elongation at break (EB) improved drastically to 133.47%, enhancing flexibility. Also, the PSOF formulation exhibited outstanding barrier efficacy, reducing water vapor permeability to 0.22 g·mm/m²·h·kPa. In a 30-day vitro food model trial, both active formulations functioned as effective oxygen barriers, markedly reducing primary lipid oxidation in packaged sunflower oil. Consequently, the integration of plant proteins with bioactive fruit seed oils presents a highly functional, oxidation-resistant, and sustainable approach for advanced active packaging applications.