Starch and amylopectin: effect of solutes on their calorimetric behavior

The gelatinization of starches and the calorimetric behavior of amylopectins in the presence of glucose, sucrose and sodium chloride were studied by differential scanning calorimetry. Increasing concentrations of sucrose and glucose increased the gelatinization temperatures. Amaranth and waxy corn starches showed higher enthalpy values than the starch from the normal corn sample. Sucrose was more effective than glucose in increasing these values. The three starches (amaranth, waxy and normal corn) used for this study showed gelatinization endotherms in the presence of sodium chloride. However, amaranth, waxy corn and commercial potato amylopectins did not show such gelatinization endotherms; only commercial corn amylopectin did. The patterns followed by starches and amylopectin with sodium chloride were similar; the enthalpy values were lower at higher salt concentrations.