Abstract: Protein-based hydrogels, characterized by their hydrophilic three-dimensional networks of cross-linked proteins, provide a promising platform for innovation in the food industry due to their excellent biocompatibility, biodegradability, and sustainable sourcing. This review systematically elucidates the progression from molecular cross-linking mechanisms to the realization of macroscopic functionalities, with a focus on the physical (e.g., thermal, pH, and ion-induced treatments) and chemical (e.g., isopeptide bonding, disulfide bonding, quinone-mediated nucleophilic addition) methods for preparing protein-based hydrogels. It further explores the innovative applications of the hydrogels as food texture modifiers, intelligent delivery systems for bioactive compounds, sustainable/intelligent packaging materials, and “bio-inks” for food 3D printing. Finally, the review critically addresses the challenges related to mechanical properties, batch-to-batch variability of raw materials, controlled release efficiency, economic viability, and safety and proposes potential solutions for the challenges, aiming to provide a forward-looking perspective on the rational design and industrial application of these functional materials.

Key words: protein-based hydrogels; food application; physicochemical mechanisms; preparation strategies