Background: Protein hydrolysates, a mixture of oligopeptides, polypeptides, and amino acids, have numerous applications in the food industry. Soy protein hydrolysates (SPHs), produced by the hydrolysis of soy protein (SP), are a common source. A diverse range of chemical and biological techniques are employed to effect the hydrolysis of soy protein. Nonetheless, these techniques have limitations, including extensive reaction times, strong acids, high pressure and temperatures, and high cost. As a result, researchers have explored other innovative approaches. Scope and approach: Ultrasound-assisted ionic liquids (UA-ILs) pretreatment, a novel non-thermal technique, can promote protein enzymatic hydrolysis. Nevertheless, there is no review on the impact of UA-ILs pretreatment on the enzymatic hydrolysis process of SP. Furthermore, there is no review of how UA-ILs impact SPH's function-ality. Hence, this review focused on recent advancements concerning the influences of UA-ILs pretreatment on the functional properties of SPHs. Safety evaluation of UA-ILs pretreatment and the IL's removal methods were discussed. Key findings and conclusion: This review showed that the synergistic effect of UA-ILs pretreatment signifi-cantly enhances the solubility, forming stability, and capacity of SPHs. Additionally, it increased the emulsifying activity and antioxidant capacity of SPHs, resulting in uniformly distributed emulsion droplets with smaller particle sizes. However, a comprehensive insight into the safety considerations of UA-ILs pretreated SPHs using in-vivo and in-vitro studies is required. This holistic understanding will provide a comprehensive assessment of the obtained pretreated SPHs.
