A surface analytical approach to the structure of starch granules

The outermost surface structure and internal structure of starch granules were linked using AFMand SEM. Within a potato starch granule, there are radial linear structures that extend from the hilum and grow wider with increasing distance from the center. The many convexoconcave structures and small raised nodules on the outermost surface of starch granules consist of aggregates of molecular chain terminals, or the minimum structural units of starches. By analyzing the outermost surface of starch granules using XPS, we obtained spectra from the Cls orbital which show lower binding energies typical of starches.