Abstract:To explore the effect of steam explosion treatment on the physicochemical properties and structure of mung bean starch，mung bean was used as raw material to investigate the effect of steam explosion pressure on the content，gelatinization characteristics，solubility and other physical and chemical properties of mung bean starch.The changes in the microstructure of mung bean starch were further analyzed by iodine absorption curve，X-ray diffraction，and Fourier transform infrared spectroscopy（FTIR）.The results showed that the content of amylose and resistant starch in mung bean was significantly higher than that of other pressure treatments when the steam pressure was 0.30 MPa（p＜0.05）. With the increase of steam pressure，the content of slowly digestible starch increased gradually，while the content of rapidly digestible starch decreased gradually. The solubility of mung bean starch decreased gradually，while its swelling power increased gradually. At a steam pressure of 0.60 MPa，the gelatinization temperature of mung bean starch reached its peak，with the lowest peal viscosity value. The microstructure analysis showed that the morphology of mung bean starch granules after steam explosion treatment changed significantly，and the relative crystallinity，short-range ordering，and double helix degree decreased.At the same time，the starch crystal form changed from A type to C type.Steam explosion treatment can change the physicochemical properties and structure of starch，and then affect the quality of mung bean starch.