The effect of extrusion process conditions on the some physicochemical properties of expanded snack based on germinated mung and corn grain

Lack of protein in developing countries specially has gained importance, recently. In recent years, due to the increased need for protein food, protein is used as a valuable food source ; so, Use of different kinds of sprouted beans in food formulation is one of the most important processing operations. In this paper, the effect of variables under investigation in the extrusion process,including temperature (120-170 degree centigrade) and screw-rotation speed (120-200 rpm), were investigated on some of the snacks features. Samples contained 16% moisture content and 20% germinated mung bean to corn grain. Features under study include expansion, porosity, hardness, and color measurement components (luminance, redness, yellowness index). The obtained results indicated that by increasing temperature and screw rotation the light, expansion, firmness, and porosity will increase, either. According to optimization results, to produce a favorable product by maximum expansion rate of 5.395, maximum porosity of 0.916, minimum texture analysis of 2.791, luminance index of 66.245, redness of 2.190 and yellowness of 24.632 a process should be established at 120 degree centigrade extrusion and 200 r/m of screw-rotation. The extruded product based on sprouted corn and mung benefits from physicochemical properties, which could supersede the current expanded stack in the market, especially for children.