Specific volume of composite bread:
The effect of Cooked Fermented Pearl Millet (CFPM) flour
on specific volume of composite bread is presented in Table 2. Bread
specific volume decreased significantly with increasing CFPM flour substitution level. The volume of bread made from composite flours, were lower than those made from pure refined wheat flour. The highest bread specific volume was 5.93 cc/g obtained from control bread, while flour containing 25 per cent CFPM flour resulted in the lowest bread specific volume of 5.04 and 5.27 cc/g, respectively. This finding was in agreement with that reported by Aluko and Olugbemi’s [11
], who found lower volumes associated with composite as opposed to 100 per cent wheat, while the specific volume of commercially available bread loaf in the market is 6 cc/g [12
Textural properties of composite bread:
The bread firmness, cohesiveness, springiness, gumminess and chewiness values was found for the composite bread with the ratio of 10, 15, 20 and 25 per cent of Cooked Fermented
Pearl Millet (CFPM) flour with the refined wheat flour. The Table 3 illustrates the textural properties of composite bread. From the table it was understood that the hardness
of the composite bread increases with increase in percentage concentration of the CFPM flour. The higher value of 21.15 N was observed for the bread with 25 per cent incorporation of the CFPM flour to the refined wheat flour. While the hardness of the remaining per cent of incorporation shows lower value [14
The hardness value of bread with 10 per cent incorporation of CFPM flour show less deviation from the control sample whose hardness was 11.48 N and the hardness of 10 per cent bread was 12.22 N. There was no remarkable difference in the values of cohesiveness and springiness in spite of any per cent of incorporation.
Effect of adding cooked fermented pearl millet flours on refined wheat flour bread and bread crumb color:
The color values L (light-dark), a (red-green), and b (yellow-blue) of the bread and crumb samples of blended flour are provided in Table 2. The results indicate that, as the per cent of CFPM flour replacement increased, L-values shifted significantly from white to gray, a values shifted from green to red, and b values shifted from blue to yellow. Overall, the L values of the bread and bread crumb samples substituted with CFPM flour decreased from 72.54 to 62.47 and from 64.54 to 55.47, indicating a significant increase in grayish color. The highest a-value was that of bread made with 25 per cent CFPM flour (-0.13); whereas, the lowest value was observed in bread made from 100 per cent refined wheat flour as indicated by a higher intensities of green color [17
]. On the other hand, the lowest b value was associated with bread made from the 100 per cent refined wheat flour 9.51, whereas the highest value 12.67 was associated with bread made with 25 per cent CFPM flour. The effects of CFPM flour substitution on the color of the bread crumb were more obvious than that of bread color. The results from this study indicate that CFPM flour darkened crumb color.
Sensory evaluation of composite breads
Semi trained panelists were given a hedonic scale questionnaire to evaluate the composite bread using a 9 points scale (1- extremely dislike, 2- dislike very much, 3- dislike moderately, 4- dislike slightly, 5- neither like nor dislike, 6- like slightly, 7- like moderately, 8- like very much, and 9 - extremely like). Composite bread was evaluated for general appearance, crumb grain, odour, softness, taste, mouth feel and overall acceptability measures.
From the Table 4 given below, it can be predicted that there was significant difference in the overall acceptability with increasing level of CFPM flour with the refined wheat flour. The color of the composite breads made with 5 and 10 per cent substituted CFPM flour was similar to the control (100 per cent refined wheat flour); whereas at higher levels of substitution, samples were significantly darker. The mouth feels score decrease significantly as the level of CFPM flour increased. The mouth feels score of 10 and 15 per cent composite bread was found to be similar with each other with the mean score of 7.59 and 7.5. The sensory evaluation score for the composite bread prepared from the 25 per cent substitution of CFPM flour in the refined wheat flour ranges from 5.22 to 6 for the sensory attributes. These results are in agreement with those reported by Summer and Nielsen, who concluded that incorporation of 25 per cent millet flour in bread formulation darkened the internal and external loaf color. In this study, overall bread quality at the different levels of cooked fermented pearl millet flour to the substitution levels from 10 to 20 per cent was found to be acceptable. However, acceptability increased as the level of substitution of CFPM flour decreased. These results are in agreement with the work of Kyomugisha [19