Biodegradable and active zein-gelatin-based electrospun mats and solvent-cast films incorporating sage extract: Formulation and comparative characterization

Abstract

This study aimed to develop active, biodegradable materials for food packaging by incorporating sage extract (SE) within a zein-gelatin blend by electrospinning and solvent casting. The fabrication techniques, SE incorporation, and its content (5, 10% w/w) determined the materials’ properties. Electrospinning produced 0.36–0.53 mm thick, non-transparent fibrous mats (mean fiber diameter 1.12–1.36 µm). Solvent casting generated 0.34–0.41 mm thick, transparent continuous films. The analysis indicated the constituents’ compatibility, homogenous dispersion, and efficient SE incorporation without strong chemical interactions and phase separation. The solvent-cast films presented more ordered structures, higher mechanical resistance, elongation, and water vapor barrier performance than the electrospun mats. The SE-incorporating formulations showed phenolics’ delivery ability to food simulants influenced by structure, SE content, and media polarity. The electrospun mats expressed higher DPPH• radicals’ inhibition, while the solvent-cast films showed stronger Staphylococcus aureus and Escherichia coli growth inhibition, increased by SE incorporation. All formulations showed rapid complete bio-disintegration in compost (18–25 days).