抄録
Starches from a very wide range of botanical materials have been isolated. Amylose contents of starches were measured by potentiometric titration of their iodine-binding capacities. The amylose contents of nonwaxy starches are in a range of 15% (rice) to 30% (pea). The iodine staining properties of amylose of a range DP 16 to 330 have been examined in terms of color, intensity of stain, and wave length of peak light absorption. Under the standard conditions used, amylose of DP 21 give a red color with a absorption peak at 510 nm, 28 purple 540, 34 violet 560, 41 blue violet 580, and 61 to 330 blue with 600 to 630 nm, respectively. Starches of corn, potato, kidney bean, sorghum and waxy rice have been fractionated into their component amylose and amylopectin. During the fractionation procedure, a fraction (C-fraction), which is precipitated by forming a complex with isoamylal cohol but not with n-butanol, was fractionated from corn-, kidney bean- and sorghum starches, respectively. Their properties have been investigated in detail. The properties of C-fraction show that they are essentially similar to amylopectin in nature. We studied the raising properties of the Japanese special confections "Arare" and"Okaki" which raise vigorously by themselves without any aids of gasses produced by fermentation or baking. Moreover, a method for the analysis of sugar mixtures containing glucose, fructose, sucrose, maltose, lactose and dextrin was investigated.
