INNER STRUCTURE OF POTATO STARCH GRANULES

A combination treatment (dry-heat and glucoamylase) was applied on pot ato starch granules. Many inner granules in the granules after the tre atments were observed by SEM. The inner granule located near edge of e llipsoid of granule was partially degraded X-ray diffraction pattern o f starch granules did not change before and after the treatments in sp ite of over 50% loss by amylase digestion. GPC and iodine reaction of the sample showed the treatments brought about fairly large degradatio n of both amylopectin and amylose components, but GPC of debranched sa mple after the combination treatments showed amylose was thoroughly de graded while peaks pattern of amylopectin did not change. Small size g ranules were more susceptible than large size granules by the treatmen ts.