Some Physico-Chemical Properties of Oat Starches Extracted from Varieties with Different Oil Content

Publisher Website
Google Scholar
Abstract
The rheological and thermal properties of four oat varieties with different oil content in the grain were studied. Rheological oscillatory measurements showed that the oat starches were less rigid (lower G') and less elastic (higher δ) compared to maize or wheat starches under the same conditions. The oat variety with the highest oil content, Chicauhua, was closest to the wheat starch in its rheological properties. Differential scanning calorimetry (DSC) showed that among the oat starches the gelatinization enthalpy was very similar, but compared to maize or wheat it was lower. The oat starches had 2–3 times higher enthalpy value for the transition of the amylose-lipid complex than maize or wheat. As measured with the DSC the native oat starches showed low retrogradation compared to normal maize but on the same level as high-amylose maize. The variety with the highest oil content, Chicauhua, retrograded least of all starches investigated. Retrogradation study on two defatted oat varieties, Chicauhua (high in oil) and Svea (low in oil) did not show a clear relation between oat oil and retrogradation tendency as small difference was found between native and defatted Svea oat starch and large difference between native and defatted Chicauhua oat starch.