Enhanced Active Packaging Properties Through the Incorporation of Pomegranate Seed Oil Micro- and Nanoparticles

Abstract

Biodegradable cassava starch–based films incorporating micro- and nanoparticles of pomegranate seed oil (PSO) were developed to enhance active packaging performance. Films were prepared via casting and characterized for physical, optical, mechanical and antioxidant properties. Nanoparticles generated thicker (0.118 mm, FLN4:1), denser films with smooth (1.68 g/cm3), homogeneous surfaces, whereas microparticles produced thinner, more soluble (up to 46.62% for FLM4:1) and opaque films with surface irregularities and agglomerates. Both systems enhanced UV light barrier properties, crucial for protecting oxidation-sensitive foods. Importantly, FTIR analyses demonstrated the preservation of chemical integrity post-processing. Mechanical performance varied according to the type of particle incorporated. The nanoparticle-based film (Fb-LN) exhibited the highest tensile strength (8.42 MPa) and stiffness (129 MPa), whereas the microparticle-loaded films (FLM series) demonstrated superior flexibility, reaching elongation values up to 236.9%. Antioxidant assessments revealed that encapsulation preserved PSO bioactivity. Films with nanoparticles (FLN4:1) demonstrated faster release (19.9% DPPH inhibition at 0.26 mg/mL) and higher immediate antioxidant activity, whereas microparticle-loaded films (FLM1:1) provided superior retention and sustained release (20.4% at 0.65 mg/mL). Particle type and size were determinants in modulating film functionality and release behaviour. Overall, PSO micro- and nanoparticle-loaded starch films offer versatile solutions for active food packaging, combining biodegradability, improved barrier and mechanical properties and controlled antioxidant release. The approach enables tailored film design to meet specific shelf life and product preservation requirements.