Effect of granule size on the structure and digestibility of jackfruit seed starch

Jackfruit seed starch (JSS), maize starch (MS) and potato starch (PS) were fractionated and separated by glycerol-assisted centrifugal sedimentation based on their size. The digestibility and structure characteristics of the fractionated starch granules were analyzed. Different starch fractions exhibited different particle morphology. There was a significant increase in the resistant starch (RS) content and relative crystallinity (RC) of the fractionated starches with the increasing granule size. The different-sized fractions of JSS, MS and PS possessed similar crystalline type and the value of R1047/1022, respectively. However, the effect of granule size on the amylose content (AC) of the same starch type was mainly manifested difference in the large- and small-sized granules. Furthermore, for all the starch samples, JSS showed the smallest granules, the highest short-range ordered level and the value of RC. Compared with MS and PS, higher resistance to digestion was shown on JSS.