Unlocking the potential of rice bran protein: modification strategies and functional enhancements

Rice bran protein (RBP) is a high-quality plant protein with balanced amino acids and low allergenicity, but its industrial application is hindered by poor solubility and limited functionality. This review provides a critical analysis of modification strategies designed to overcome these challenges, categorizing them into physical, chemical, and biological approaches. Physical methods (e.g., ultrasound, high-pressure processing, extrusion) disrupt non-covalent interactions to improve solubility and interfacial properties. Chemical techniques, such as glycosylation and phosphorylation, enhance functionality through covalent conjugation, markedly improving emulsifying stability and solubility. Biological methods, including enzymatic hydrolysis and cross-linking, enable precise structural tailoring under mild conditions. A key contribution of this work is the introduction of a comparative, application-driven framework that systematically evaluates the efficacy, technological trade-offs, and optimal food applications of each method. The analysis highlights that the choice of modification must balance functional performance with considerations of scalability, cost, and clean-label requirements. Finally, future research priorities are identified, emphasizing the need for synergistic hybrid processes, performance validation in complex food matrices, and scalable process engineering. This comprehensive synthesis aims to guide the rational development of RBP as a sustainable, high-value functional ingredient for the food industry.