Rheological Characterization of Grain Legume Pastes and Effect of Hydration Time and Water Level on Apparent Viscosity

Abstract

ABSTRACT An extrusion capillary viscometer was employed to obtain shear stress‐shear rate data of two types of cowpea pastes, traditional and experimental. The power law model was found to describe adequately flow behavior of the pastes with consistency coefficients of 77.45 and 59.02, and flow behavior indices of 0.456 and 0.458 for experimental and traditional pastes, respectively. Effect of hydration time (0 ‐ 180 min) and water level (54 ‐ 62%) on the apparent viscosity of experimental paste was determined by extrusion capillary and Brookfield viscometers with correlation coefficient of 0.953. Water level had a significantly greater effect than hydration time on apparent viscosity of cowpea paste.