Some properties of starches of grain amaranths and several millets

Starch granules were prepared from seeds of Amaranthus hypochondriacus L., A. caudatus L., proso millet, Japanese barnyard millet and foxtail millet. Amylose contents and the distribution of alpha-1,4 linked chain of amylopectin were determined by gel filtration of isoamylase-debranched starches. Some physical and chemical properties of the starches were also examined by scanning electron microscopy, X-ray diffractometry, photopastegraphy, and differential scanning calorimetry, together with starch-granule susceptibility to amylases. The existence of both normal and waxy types in the same species of a grain amaranth, A. hypochondriacus L., was confirmed. A. caudatas starches were identified to consist of mainly typical amylopectin and 5-7% amylose. The starches have some unique properties, namely, high starch-granule susceptibility values to amylases as well as those of A. hypochondriacus and unique pasting properties.