| Abstract: | Heat/moisture-treated potato and corn starch granules were observed by microscopy and X-ray diffraction patterns were obtained. A scanning electron microscope (SEM) photograph of the cross section of the heat/moisture-treated potato and corn starch granules showed a large hollow area about 1/3 of the diameter at the center of the starch granules and a layered structure resembling growth rings. From the X-ray diagrams it was confirmed that heat/moisture-treatment caused an alteration from the B-type in the direction an A-type structure in potato, whereas corn starch did not change and maintained an A-type structure. The enzymatic digestibility of heat/moisture-treated starch was found to be less resistant than that of native starch. |
