Abstract:Buckwheat flour was used as raw material to extract buckwheat protein by alkali extraction and acid precipitation. The effects of extrusion and microwave modification on the structure and physicochemical properties of buckwheat protein were studied. The results showed that the conformation of buckwheat protein could be affected by extrusion and microwave modification. The molecular weight of natural buckwheat protein was mainly in the range of 22.4-58.7 kDa， and the 58.7 kDa protein bands disappeared after extrusion modification. The secondary structure of the modified buckwheat protein changed from β-sheet to α-helix structure，and random curling was the main component. The fluorescence intensity of buckwheat protein reached the maximum after the change of the tertiary structure and microwave modification. The modification had a significant effect on the physicochemical properties of buckwheat protein. The surface hydrophobicity of buckwheat protein after microwave modification was increased by 191%， and the emulsifying activity and stability of buckwheat protein after modification were 28.93 m2/g and 614.392 min. Extrusion and microwave modification were both safe and effective ways to modify buckwheat protein. Compared with extrusion modification， microwave modification had a more significant effect on the structure and physicochemical properties of buckwheat protein.