Heat-induced structural changes of small and large barley starch granules

Abstract

The small granules of barley starch were shown to differ from the large granules both in chemical composition and heat-induced functional properties. The small granules had a higher lipid:amylose ratio and also higher dissociation enthalpy of the amylose-lipid complex than the large granules. This may explain the better stability of amylopectin in the gel of small starch granules as analysed by DSC. The small granules had a 4°C higher gelatinisation temperature than the large granules. During heating up to 90°C, the fraction obtained by aqueous leaching of small granules was mainly amylopectin, whereas the carbohydrate solubilized from large granules was mainly amylose.