Physical and Water Absorption Characteristics of Some Improved Rice Varieties

The physical and water absorption characteristics of paddy and brown rice from some early maturing Oryza sativa varieties and newly developed interspecific (O. sativa × Oryza glaberrima) rice varieties were studied. The physical dimensions (length, breadth and width, length/width ratio, equivalent diameter), grain surface area and volume, sphericity, 1,000-kernel weight, bulk and true densities as well as porosity were determined. A nonlinear moisture diffusion equation was used to model the water absorption curves of the rice varieties at 30–60 °C. Digital images of the rice grains were analyzed for their tristimulus color parameters (L*, a*, b*). The physical characteristics of the rice varieties differed significantly (p