Abstract
SDF (soluble dietary fiber) and IDF (insoluble dietary fiber) fractions were extracted from 14 different foods by the modified Prosky method. Ion exchange chromatography with DEAE cellulose was employed to examine each of the fractionated sugars. Aloe fractions were further subjected to gel chromatography to examine the effect of heating on molecular weight. The SDF fractions of anhydrous samples of okra, cabbage, celery, bitter gourd, and carrot were large when autoclaved, while that of aloe was largest when unheated, and those of eggplant, edible burdock, Japanese radish, hijiki, and nameko were large when microwaved. The SDF fractions of moroheiya and okra included acid polysaccharides in large quantities, and acid polysaccharides increased further with autoclaving. The SDF fraction of celery did not show as pronounced a tendency for heat-induced increase of acid sugar. IR analysis confirmed that heating affected the functional groups of this fraction.
