Physico-chemical characteristics of extruded snacks prepared from rice (Oryza sativa. L) and chickpea (Cicer arietinum. L) by single screw extrusion

Rice and chickpea blends were used to prepare snack products. On increasing the proportion of chickpea in the blends, the diametric expansion(DE) and water holding capacity (WHC) decreased, while peak shear force (PSF) and bulk density (BD) increased. Sodium dodecyl sulphate (SDS) plus 2-mercaptoethanol (ME), containing phosphate buffer (pH 6.9) were found to extract more protein than SDS or plain buffer solution from the extrudates. Loss of carbohydrates was documented after extrusion of feeds, containing >50% carbohydrates and >30% proteins. In products with high DE and low PSF, air cells were predominant and smooth surface morphology was evident as observed from the scanning electron microscopy (SEM).