From wastes to functional materials: Preparation, modification, and applications of polysaccharide-based...

Food processing byproducts like fruit pomace and crustacean waste are rich in polysaccharides but remain underutilized. Direct disposal wastes resources and pollutes the environment. Efficient extraction and conversion into high-value products (e.g., biodegradable films) are crucial for reducing plastic pollution and promoting sustainability. This review highlights recent advances in polysaccharide extraction and biodegradable film production, covering techniques, functional design, and applications. The review examines polysaccharide extraction from fruit pomace (using ultrasound, microwave, and enzymatic methods) and crustacean waste (via enzyme-assisted extraction and ionic liquid treatment). For film fabrication, solution casting, extrusion blow molding, electrostatic spinning, 3D printing, and layer-by-layer self-assembly techniques are analyzed, alongside enhancement strategies like polymer blending, nanocomposites, and cross-linking. Functional designs include active packaging (antimicrobial/antioxidant) and stimuli-responsive films (color/property changes). Functional films extend food shelf life (active packaging), monitor freshness (stimuli-responsive), protect wounds (medical dressings), and enhance crop productivity (agricultural mulches). However, scaling production and cost control remain challenges. Future research should optimize processes, enhance stability, and assess economic feasibility to enable commercialization.