Effect of Thermal Treatment on Selected Cereals and Millets Flour Doughs and Their Baking Quality

Selected cereals (rice and sorghum) and millets (finger millet and pearl millet) were steamed for 20 min at ambient pressure. The rheological properties of doughs, made from these steamed as well raw grain flours, were characterized in addition to examining their baking quality. The two-cycle compression test was employed and instrumental values were correlated with sensory attributes (color, aroma, taste, stickiness, chewiness, tearing strength, cohesiveness, and rollability) using principal component analysis (PCA). Rice doughs made from both raw as well as thermally treated flour imparted maximum hardness (96.6–99.3 N) and least cohesiveness (0.05–0.09) with highest stickiness values (105–110°) among all the dough samples at the same moisture content. Pearl millet and raw sorghum flour doughs possessed the least instrumental hardness, adhesiveness, and stickiness and were the easiest to flatten. The PCA biplot showed that sensory and instrumental cohesiveness formed a cluster on the left side on the x axis while shear force, and sensory attributes like tearing strength, chewiness, stickiness, and rollability formed another cluster on the other side of the axis. Raw rice and finger millet doughs were associated with the high extent of instrumental and sensory stickiness. Thermally treated pearl millet and sorghum doughs were the best followed by treated rice and finger millet samples to give the desirable dough characteristics, and were quite close to wheat chapathi in texture.