MOLECULAR-WEIGHT CHARACTERIZATION AND GELLING PROPERTIES OF ACID-MODIFIED MAIZE STARCHES

The reduction in the molecular weight distribution during acid hydrolysis of ordinary and waxy maize starch occurred in two stages: first amylopectin degraded to intermediate high molecular weight polysaccharides, secondly, these were further hydrolyzed. The amylose moiety of ordinary and high-amylose starch was not affected very much by the hydrolysis conditions used (0.1-1 M HCl, 40-degrees-C, 0.3-4 h), but the gelling properties of starch weakened. The amylopectin degradation products, probably branched dextrins, were shown to hinder the gel formation of amylose in the starch pastes