Author:

Keywords:

Science & Technology, Life Sciences & Biomedicine, Physical Sciences, Biochemistry & Molecular Biology, Chemistry, Applied, Chemistry, Organic, Chemistry, Rye starch, Wheat starch, Amylose/amylopectin fractionation, Amylopectin structure, Gelatinisation, Pasting, ASPECTS PROVIDE INSIGHT, ANION-EXCHANGE CHROMATOGRAPHY, PULSED AMPEROMETRIC DETECTION, CHAIN-LENGTH DISTRIBUTION, PASTING PROPERTIES, RICE STARCHES, AMYLOPECTIN RETROGRADATION, ENVIRONMENTAL-TEMPERATURE, GELATINIZATION PROPERTIES, INTERMEDIATE MATERIALS, Amylopectin, Calorimetry, Differential Scanning, Chromatography, Gel, Crystallization, Dextrins, Flour, Molecular Weight, Particle Size, Secale, Starch, Transition Temperature, Triticum, Viscosity, 0304 Medicinal and Biomolecular Chemistry, 0305 Organic Chemistry, 0601 Biochemistry and Cell Biology, Organic Chemistry, 3101 Biochemistry and cell biology, 3405 Organic chemistry

Abstract:

The gelatinisation, pasting and retrogradation properties of three rye starches isolated using a proteinase-based procedure were investigated and compared to those of wheat starch isolated in a comparable way. On an average, the rye starch granules were larger than those of wheat starch. The former had very comparable gelatinisation temperatures and enthalpies, but slightly lower gelatinisation temperatures than wheat starch. Under standardised conditions, they retrograded to a lesser extent than wheat starch. The lower gelatinisation temperatures and tendencies of the rye starches to retrograde originated probably from their higher levels of short amylopectin (AP) chains [degree of polymerisation (DP) 6-12] and their lower levels of longer chains (DP 13-24) than observed for wheat starch. The rapid visco analysis differences in peak and end viscosities between the rye starches as well as between rye and wheat starches were at least partly attributable to differences in the levels of AP short chains and in average amylose molecular weight. The AP average chain lengths and exterior chain lengths were slightly lower for rye starches, while the interior chain lengths were slightly higher than those for wheat starch.