Sodium Alginate/Pectin/Gelatin-Based Biopolymer Films Fortified with Pomegranate Peel Extract

For the fabrication of advanced packaging matrices with enhanced barrier performance and extended product shelf life, bioderived materials offer sustainable alternatives to conventional nonbiodegradable polymers. This study aimed to fabricate and systematically evaluate sodium alginate (SA)/pectin (P)/gelatin (G) films incorporated with 0-2% (w/w) pomegranate peel extract (PPE) with respect to their mechanical, physical, barrier, thermal, and morphological characteristics. A significant (p ≤ 0.05) enhancement in thickness, tensile strength (TS), and elastic modulus (EM) was observed in SA/P/G-based films with increasing concentrations of PPE. Conversely, increasing the concentration of PPE in the films led to a significant (p ≤ 0.05) and progressive reduction in moisture content (MC, %), water solubility (WS, %), water vapor permeability (WVP), elongation at break (EAB, %), and light transmittance across all formulations. Incorporation of 0.5-2% PPE into SA/P/G films enhanced thermal stability as shown by DSC, improved cross-sectional compactness observed via SEM, and significantly increased DPPH and ABTS radical-scavenging capacities to 85.64 and 78.76% through protein-polysaccharide-polyphenol interactions. The study demonstrated that SA/P/G-based films incorporating PPE represent a viable eco-friendly alternative to conventional packaging materials.