Currently, the low efficiency and pollution issues associated with biological and chemical methods for the preparation of functional peptides continue to pose challenges, restricting the large-scale production and utilization of functional peptides. This study has found that the ultrasound-assisted organic acid-surfactant system is an efficient and green method for the preparation of functional peptides. The probe ultrasonication-assisted tartaric acid system successfully degraded oat globulins into peptides with a degree of hydrolysis (DH) of 22.8 %. The addition of glyceryl monostearate increased the instantaneous burst rate of the bubble (with a D-value of 16 %), thereby elevating the DH to as high as 36 %. The resulting oat peptide particles exhibited high hydrophobicity, and consequently demonstrated strong foaming capacity (99.6 %), oil holding capacity (399.4 %), emulsifying ability (Emulsifying activity index = 50.5 m