Abstract:

Five kinds of dietary fibers from soybean dregs, including water-soluble dietary fiber (SDF), water-insolubledietary fiber (IDF), pectin, hemicellulose A (HCA) and hemicellulose B (HCB) were used to explore their in vitro adsorptioncapacity for glucose, acrylamide, NO2－ and heavy metals, respectively. The results showed that the adsorption capacitywas highly related to dietary fiber type, adsorbate type and pH. Compared to insoluble constituents (IDF and HCA),the soluble ones (SDF, pectin and HCB) had stronger adsorption capacity for glucose, acrylamide, NO2－ and heavymetals such as Pb, Cu, Cd and Zn. As for adsorbate type, soybean dietary fibers adsorbed more glucose, NO2－ andheavy metals than acrylamide. The adsorption capacity of soybean dietary fibers for NO2－ and acrylamide was better insimulated stomach fluid (pH 2) than in simulated small intestine fluid (pH 7), while heavy metals was adsorbed betterin simulated small intestine fluid.

Key words: dietary fiber, adsorption capacity, glucose, acrylamide, NO2－, heavy metals