Effects of Extrusion Operating Conditions and Blend Proportion on the Expansion Properties of Sorghum-Barley-Chickpea blend Extruded Products

Abstract:

Extrusion cooking is a versatile and well-established food process that is used to make ready-to-eat snack foods. In this study, Response surface methodology was used to evaluate the effect of feed parameters i.e., moisture content (8-16%), blend ratio of sorghum:barley:chickpea flours (70:15:15 to 50:35:15) and machine parameters i.e., barrel temperature (120-200 oC) and screw speed (120-200 rpm) on expansion propertiesi.e., longitudinal expansion index (LEI) and volumetric expansion index (VEI) of extrudates developed by twin screw extruder. The results showed that LEI ranged from 0.64 to 1.46 mm and VEI ranged from 1.17 to 3.38 mm. The results reveals that extrudates characteristics were significantly influenced by feed moisture content and barrel temperature, with feed moisture content having the greater impact.