Observations on retrogradation of starch polymers in the presence of wheat and rye arabinoxylans

Abstract The effect of addition of wheat and rye water-soluble arabinoxylans on the retrogradation kinetics of concentrated amylose (20% w/w), wheat, and waxy maize starch (40% w/w) gels was investigated. Arabinoxylans added at a low concentration (1-2% w/w of total a-D-glucan) increased the crystallization rate of amylopectin, as evidenced by X-ray diffraction and calorimetry. For the amyloseand wheat starch-arabinoxylan mixtures, the storage modulus (G’) was clearly higher than the respective amylose and starch gels alone. In contrast, arabinoxylan retarded the gelation rate (G’ evolution) of waxy maize starch gels suggesting that this polysaccharide interferes with intermolecular cross-linking processes responsible for the rigidity of amylopectin gels; this effect was less pronounced with gels of increasing amylopectin concentration.