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Mung bean starch processed by different superfine grinding times was studied to demonstrate the effects of superfine grinding processing with high frequency vibration on its retrogradation properties. In this research, the structure and properties of Mung bean starch, such as particle size distribution and crystallinity, were analyzed. The properties of starch retrogradation, including the solubility, swelling power, retrogradation property, and retrogradation value, were studied, and the contents of resistant starch obtained by retrogradation processing were comparatively analyzed. This study provided theoretical basis and technical support for improving the content and processing technology of resistant starch in Mung bean starch products, respectively. The results show that: As the vibrating superfine grinding processing time increased from 10 to 50 minutes, the average particle size, median diameter (D50), and dispersion of Mung bean starch granules increased while the specific surface area decreased. As the vibrating superfine grinding processing time increased from 10 to 50 minutes, the feature of peak diffraction in the diffractogram gradually weakened, including the widened half peak width and decreased peak intensity. The crystallinity decreased from 32.6% to 5.4%, and the crystal ordering level decreased while its amorphous level increased. As the vibrating superfine grinding processing time increased from 10 to 50 minutes, the water solubility of the samples showed a significant increase at the same measuring temperature. Furthermore, the water solubility of the Mung bean starch also increased with increasing temperatures at the same superfine grinding processing time. With increasing processing time, the swelling power of the Mung bean starch increased at a lower temperature (25℃, 50℃) and decreased at a higher temperature (75℃, 95℃). The results showed that the effects of temperature on the swelling power weakened with the increasing processing time. The retrogradation level and rate of Mung bean starch increased with prolonged time when samples were processed using the vibrating superfine grinding within 30 minutes. However, after being processed for 40 minutes, it took a longer time for the microcrystalline starch to sedimentate. Furthermore, the solution system was opaque, and the chain segments that formed the flocculation became smaller. Although the sedimentation volume decreased, the conclusion that the retrogradation capabilities had improved could not be made. As the vibrating superfine grinding processing time increased from 10 to 50 minutes, the retrogradation value of Mung bean starch increased and reached its peak value at 20 minuets and then decreased gradually. The moderate time for superfine processing improved the retrogradation level of Mung bean starch. However, the starch molecules were hard to recrystallize and retrogradate after long-time superfine processing and formed stable starch paste. As the vibrating superfine grinding processing time increased, the resistant starch content of Mung bean increased and reached its peak value at 20 min and then decreased. The moderate time for superfine processing could improve the formation of the resistant starch of Mung bean. It was not a simple physical refining process for starch to be processed by superfine grinding with high frequency vibration. It was a homeostasis process that changed the complex energy conversion and starch properties. Therefore, the processing time was particularly important for the changing of the sample’s properties in the superfine processing of Mung bean starch. [ABSTRACT FROM AUTHOR]