Emulsion-gelatin electrospinning core-shell nanofibers with cinnamaldehyde crosslinking: A novel strategy for enhanced stability and bioaccessibility of α-linolenic acid

Emulsion-electrospinning strategy encapsulated ALA in gelatin-based nanofibers. • Core-shell structure effectively shielded the lipid within the nanofiber matrix. • Cinnamaldehyde crosslinking enhanced physicochemical properties of nanofibers. • Crosslinked fibers enabled the sustained release of ALA during digestion. • Bioaccessibility of ALA increased from 29.5% to 78.2% with the optimized system. The application of α-linolenic acid (ALA) is hindered by oxidative instability and poor bioaccessibility. Herein, ALA was encapsulated in core-shell gelatin nanofibers via emulsion electrospinning, integrated with in situ cinnamaldehyde (CA) crosslinking for the first time. Increasing the emulsion-to-gelatin ratio from 1:2 to 1:6 reduced droplet size from 2.86 to 1.83 μm, yielding uniform nanofibers (135.8–347.6 nm). CA-crosslinking reinforced the structural network through localized coalescence. Microscopy confirmed distinct core-shell nanofibers with ALA shielded within the gelatin matrix. Spectroscopy and molecular docking revealed CA-induced Schiff base reactions and hydrogen bonding, which increased mechanical strength from 3.67 to 6.66 MPa. CA treatment also improved surface hydrophobicity and reduced water solubility. The optimized formulation EG14A achieved high encapsulation efficiency (92.3%), sustained release during in vitro digestion, and elevated ALA bioaccessibility to 78.2%, while maintaining good biocompatibility. This integrated approach provides a novel, food-grade platform for stabilizing and delivering sensitive bioactive lipids. Download: Download high-res image (158KB) Download: Download full-size image