Crosslinking Soy Protein: Mechanisms, Functional Modification, Applications in Food, and Future Directions

Soy protein (SP) is a sustainable plant‐based biopolymer valued for its nutrition, yet its application is often restricted by poor solubility, instability, and reduced bioavailability. Crosslinking overcomes these limitations by forming intra‐ and intermolecular covalent bonds, thereby altering the protein's structure and functionality. This review analyzes enzymatic (e.g., transglutaminase, laccases), chemical (e.g., genipin, tannins), and physical (e.g., high‐pressure, thermal) crosslinking mechanisms. These modifications significantly enhance functional properties, including emulsion stability, gel strength, and water‐holding capacity. These improvements enable advanced applications in texturized foods like meat analogs, functional emulsions, active/biodegradable packaging films, and bio‐based adhesives. Despite the promising advancements, challenges regarding scalability, cost, off‐flavors, and regulation persist. Future directions point towards the integration of hybrid modification techniques, AI‐driven process optimization, and the development of smart, bioresponsive materials to fully realize the potential of crosslinked SP as a high‐performance, sustainable ingredient in the food and industrial sectors.