ABSTRACT
The investigation was carried out to evaluate the effect of some raw materials, rich in protein content on the quality characteristics of extrudates produced from yellow corn girts. Seven preparations of fortified yellow corn grits were blended using defatted peanut and sesame or chichpea flours with yellow corn grit at two levels i.e. 15% and 20%, in order to produce good and nutritional extrudates, Physical characteristics such as water absorption index [WAI], water solubility index [WSI], bulk density [BD] diameter, expansion ratio [ER]; shear force [SF], and sensory properties were evaluated after processing [zero time], and during three months storage at room temperature [31 +/- 2°C] Chemical analysis of raw materials indicated that, the highest contents of protein, total hydrolyzeable carbohydrates fiber, lipids and ash were found in defatted peanut, yellow corn girts, defatted sesame, chickpeas flour, and defatted sesame flour, respectively. Characteristics of the extrudates were varied according to type of blends and the fortification level. Yellow corn grits fortified with 20% defattet peanut or sesame flour had the highest percent increase of WAI, and WSI, meanwhile there were similar results in the BD, ER and diameter. The extruded control followed by the blends fortified with 15% or 20% chickpeas flour gave both of the highest diameter, and expansion ratio value, compared to blends containing 15% defatted peanut flour. Sensory evaluation revealed that the best taste scores, chewiniss values, pore distribution and porous texture, colour and surface characteristics and general appearance of extrudates occurred in the extrudates fortified with 15% or 20% defatted peanut, sesame or chickpeas flours, and were found to be significantly better than the other blends. Generally, all sensory evaluation scores, values of Hunter colour measurements [L, a and b] of the extrudates decreased gradually during storage for three months at room temperature for all extruded products especially with blends containing peanut or sesame flour at levels of 15% or 20%