Physicochemical properties of Pinhão ( Araucaria angustifolia, Bert, O. Ktze) starch phosphates

Abstract

Physicochemical properties of pinhão (seeds of Paraná pine) starch phosphates were evaluated and compared to corn starch phosphates. The phosphorylation process used yielded starch phosphates with three different degrees of substitution (DS): low (0.015), medium (0.07) and high (⩾0.12). Medium and high DS starch phosphates had higher cold water binding capacity, swelling power, and paste clarity, but lower paste syneresis (at 5 °C and after freeze–thaw cycles) than native starches ( P<0.05). Low, medium, and high DS corn starches had higher solubility than native starches (3.8-, 8-, and 6-fold higher; P<0.05), but the solubility of pinhão starch increased only in medium DS starch phosphates (3-fold higher; P<0.05). Low DS starch phosphates had viscosity curves similar to native starches. In contrast, medium and high DS starch pastes had peak viscosity at room temperature, reached the minimum viscosity when heated to 95 °C, and had low setback.