Abstract
Starch granules were prepared from 8 kinds of acorn; Kunugi (Quercus acutissima Carruth), Konara (Q. serrata Thunb), Naragashiwa (Q. aliena Blume), Shirakashi (Q. myrsinaefolia Blume), Matebashii (Lithocarpus edulis Nakai), Tuburajii (Shiia cuspidata Makino), Arakashi (Q. glauca Thunb), and Sutajii (Shiia Sieboldii Makino, Castanopsis cuspidata Schottky var. Sieboldii Nakai). Granular sizes, contents of the apparent amylose (26-28%), and chain length distributions of amylopectin of the acorn starches are similar to those of maize starch. Chain length distributions measured by HPAEC-PAD showed that amylopectinns of Sudajii and Tsuburajii starches had low amounts of chains with DP 9-17 in comparison to maize starch and the other acorn starches. Each acorn starch showed different gelatinizing temperature by DSC; those of Arakashi and Tuburajii starches had lower values similar to potato starch and that of Kunugi had higher values similar to sweet potato starch. On the heats of gelatinization the acorn starches were different from rice and maize starches and similar to potato and sweet potato starches. Peak viscosities of the acorn starches by RVA were higher than rice and maize starches and similar to sweet potato and wapoto starches.
