From Structural Regulation to Functional Applications: Microcrystalline Cellulose in Sustainable Food Packaging and Food Additives

Abstract

Microcrystalline cellulose (MCC) has attracted increasing interest in food systems because of its renewable origin, high safety, processing adaptability, and physicochemical stability. As an approved food additive, MCC can function as a thickener, stabilizer, gelling agent, texture modifier, and structural component in biodegradable food packaging materials. However, native MCC contains abundant surface hydroxyl groups and exhibits strong hydrophilicity, poor dispersibility in nonpolar media, and limited compatibility with complex food matrices and hydrophobic packaging systems. To address these limitations, this review summarizes recent advances in the physical and chemical modification of MCC, including esterification, covalent grafting, graft copolymerization, cross-linking, and silylation, with emphasis on the regulation of surface polarity, interfacial compatibility, and colloidal behavior. Following a framework linking structural regulation, functional mechanisms, and application scenarios, this review discusses the role of MCC in two major food-related fields: sustainable food packaging and functional food additives. In packaging systems, MCC acts as a biobased reinforcing and functional phase that improves the mechanical strength, barrier performance, and preservation capacity of polysaccharide-, protein-, and polyester-based films. In food formulations, MCC contributes to texture optimization, water regulation, emulsion stabilization, fat replacement, and antioxidant-assisted functionality through particle reinforcement, network formation, interfacial adsorption, and physical filling effects. Emerging applications of MCC in Pickering emulsions, three-dimensional food printing, and enzyme immobilization are further highlighted. Finally, key challenges related to food-grade surface engineering, sensory and safety boundaries, matrix compatibility, and real-food validation are discussed, with the aim of supporting the translation of MCC from a conventional cellulose ingredient into a multifunctional platform for sustainable food formulation and packaging.