Effect of amylose content on gelatinization, retrogradation, and pasting properties of starches from waxy and nonwaxy wheat and their F1 seeds

We studied the effect of amylose content on the gelatinization, retrogradat ion, and pasting properties of starch using wheat starches differing in amy lose content. Starches were isolated from waxy and nonwaxy wheat and recipr ocal Fl seeds by crossing waxy and nonwaxy wheat. Mixing waxy and nonwaxy w heat starch produced a mixed starch with the same amylose content as Fl see ds for comparison. The amylose content of Fl seeds ranged between waxy and nonwaxy wheat. Nonwaxy-waxy wheat had a higher amylose content than waxy-no nwaxy wheat. Endothermic enthalpy and final gelatinization temperature meas ured by differential scanning calorimetry correlated negatively with amylos e content. Gelatinization onset and peak temperature clearly differed betwe en Fl and mixed starches with the same amylose content as Fl starches. Enth alpy for melting recrystallized starches correlated negatively with amylose content. Rapid Visco Analyser measurement showed that Fl starches had a hi gher peak viscosity than waxy and nonwaxy wheat starches. Mixed starches sh owed characteristic profiles with two low peaks. Setback and final viscosit y correlated highly with amylose content. Some of gelatinization and pastin g properties differed between Fl starches and mixed starches.