Electrospinning and electrospraying of carotenoids: Materials, methods, and process framework

Abstract

Carotenoids exhibit potent antioxidant and provitamin A activities yet face severe formulation constraints due to hydrophobicity, environmental lability, and limited bioavailability. Electrospinning and electrospraying generate solid-state amorphous dispersions and core-shell architectures under mild thermal conditions, physically isolating carotenoids from oxygen, light, and heat while enhancing apparent solubility. A rheological decision boundary governed by solution viscosity and polymer chain entanglement dictates structural outcome: high-viscosity formulations yield continuous nanofibers suited for active packaging and sustained release, whereas low-viscosity systems produce discrete particles ideal for beverage fortification and rapid dispersion. Hydrocarbon carotenes integrate effectively into hydrophobic protein matrices such as zein, while polar xanthophylls and ketocarotenoids demonstrate superior stability in polysaccharide-protein blends, with encapsulated forms consistently retaining 70-90 of initial content during storage compared to rapid degradation of free pigments. Release kinetics are tunable through matrix design, crosslinking, or multilayer architectures, enabling diffusion-controlled delivery aligned with gastrointestinal transit. Translational adoption remains constrained by residual solvent toxicity, regulatory uncertainty regarding nanomaterial migration into food matrices, and limited throughput of single-nozzle configurations. Emerging pathways toward commercial viability include food-grade green solvents and deep eutectic systems, multi-jet or needleless electrohydrodynamic platforms, and stimuli-responsive polymers for site-specific release. Integration of mechanistic polymer-carotenoid design principles with scalable processing represents a critical step toward regulatory-compliant delivery systems for functional foods and nutraceuticals.