AbstractIn this study, the compositions, structural properties, and digestive characteristics of green wheat starch (GWS) and its isolated A‐ and B‐type starch granules are analyzed and compared with their mature wheat starch (MWS) counterparts. The proportion of small granules in GWS is higher than that in MWS, as revealed by the particle size distribution curves. The scanning electron microscopy of GWS shows agglomeration of more granules in the presence of B‐type starch. The predicted glycemic index (pGI) ranged from 76.20 to 86.35 for different types of starch, and the lowest and highest pGIs are obtained from B‐type granule in GWS and B‐type granule in MWS, respectively. According to the analysis of differential scanning calorimetry, GWS and its A‐ and B‐starch granules demonstrates higher gelatinization temperatures (To, Tp, and Tc) and enthalpy than those of their MWS counterparts. The X‐ray diffraction pattern reveals the A‐type pattern of crystalline starch for all the starch samples, where the crystallinity index of GWS is higher than that of MWS, which is consistent with the higher relative content of double helices determined by nuclear magnetic resonance.