Modelling the flowing behaviour of dika kernel powder and soup as affected by moisture content, physical and rheological properties

摘要

Dika kernels are known for their mucilaginous consistency, but limited work has been reported about it. This study investigated the flowing characteristics (share stress and viscosity) of the dika kernel and its soup; and this was assessed at specific temperatures (30, 50, 70 and 90) degrees C by the use of a viscometer. All samples behaved as non-Newtonian fluids. The bulk, tapped and loose densities of the powdered samples were obtained to evaluate the Carr index, Hausner ratio and porosity. The viscosity and shear stress of the reconstituted powder and soup samples as a function of the shear rate were investigated (30-90 degrees C). Dika kernel at its natural moisture content has excellent flowing property (1.118 Hausner ratio, 10.566 Carr index and 20.300% porosity), but increase in moisture content decreased this ability. The viscosity of the soup (165.789-14,546.341 mPa s) was higher than the reconstituted dika (69.831-206.240 mPa s) at all temperature studied. Shear stress was temperature-dependent, and Bingham and Power-law models gave the best predictions of flow.