Abstract
Some physicochemical properties of starch granules prepared from bulbs of Katakuri, which were collected in Akita Prefecture, were investigated. The average particle size of Katakuri starch was 24.3μm, which was smaller than that of potato starch (36.5μm) and edible canna starch (37.1μm). The susceptibility of Katakuri starch granules to hog pancreatin was higher than that of potato and edible canna starches, stripe structure and large holes on the center of which were observed by scanning electron micrographs (SEM). The amylose content of Katakuri starch was 22.8%. Average chain lengths of fraction II and III, determined by enzyme-chromatographic method, were 47.4 and 14.6, respectively, which were longer than that of the other starches. The initiation temperatures for gelatinization of Katakuri starch by photopastegraphic, differential scanning calorimetric (DSC), Brabender's viscographic and dynamic viscoelasticity measurements, were 45.0, 46.6, 54.2 and 47.0°C. Katakuri starch granules had high digestibility, and the initiation temperatures for gelatinization were lower than that of potato and edible canna starches by about 10°C.
