Heat-induced phenomena in soy protein suspensions. Rheometric data and theoretical interpretation

CLAUDIO L. A. BERLI, JULIO A. DEIBER, MARÍA C. AÑON

JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

American Chemical Society

Año: 1999 vol. 47 p. 893 - 900

0021-8561

Heat-induced aggregation of soy proteins in aqueous suspensions was studied through cone and plate rheometry for two different heating conditions. The rheometric data obtained covered the temperature range from 20 °C (stable colloidal suspension) to 90 °C (onset of network formation). Calorimetric data for the soy protein samples were also obtained to evaluate the degree of protein denaturation in the rheometric cell. Heat-induced transitions in soy globulins, such as dissociation, denaturation, and aggregation, were analyzed in relation to the rheological response of the suspension. The viscosity of the stable colloidal suspension satisfies the Cross model. A viscosity equation for the aggregating suspension was also derived by considering the fractal structure of the particle clusters and the Brownian aggregation mechanism. This equation is suitable to describe the experimental viscosity data.90 °C (onset of network formation). Calorimetric data for the soy protein samples were also obtained to evaluate the degree of protein denaturation in the rheometric cell. Heat-induced transitions in soy globulins, such as dissociation, denaturation, and aggregation, were analyzed in relation to the rheological response of the suspension. The viscosity of the stable colloidal suspension satisfies the Cross model. A viscosity equation for the aggregating suspension was also derived by considering the fractal structure of the particle clusters and the Brownian aggregation mechanism. This equation is suitable to describe the experimental viscosity data.