Abstract:The damaged starch content, gelatinization characteristics, particle morphology, crystal structure, digestion characteristics, freeze-thaw stability, and thermal characteristics of starch from wheat flour at different particle sizes was analyzed to explore the changes in the characteristics of starch. The results showed that as particle size decreased, damaged starch content increased by 78.11% and freeze-thaw stability increased from 33.35% to 49.19%. Regarding gelatinization characteristics, the viscosity and attenuation values showed a trend of initial decrease followed by increase, whereas the gelatinization temperature showed no significant change. The starch granules became increasingly dispersed from an agglomerated state, and surface was roughness increased. The relative crystallinity of starch first increased and then decreased, reaching a peak value of 21.78% when the grain size was 12XX/--, and exhibited a high diffraction peak intensity at medium particle size. The rapidly digestible starch content first increased and then decreased, slowly digestible starch content decreased by 22.01%, and resistant starch content was 59.88% at medium particle size. Considering starch thermal characteristics, the peak temperature increased with decreasing particle size; when the particlesize of wheat flour was 13XX/--, the initial temperature was 58.55 ℃ and the final temperature was 69.72 ℃. In conclusion, the starch characteristics of wheat flour were generally superior at medium particle size. Our findings can provide a theoretical basis for the starch production requirements of wheat flour at different particle sizes.
