Physico-chemical properties of wheat-yam flour composite bread

Abstract

This work investigated the effect of yam flour substitution on characteristics of wheat bread and also determined the functional properties of the experimental flour samples. Flours were obtained from three varieties of yam (Dioscorea rotundata, Dioscorea alata and Dioscorea bulbifera) and blended with wheat flour at 25, 50 and 75 percent levels of substitution for bread production. Wheat flour (WF) and each of the yam flours were used as the positive and negative controls respectively. The functional properties (bulk density, water/oil absorption capacities, emulsion activity) of the flour samples were determined while the proximate, physical and sensory characteristics of loaves were also determined. The functional properties of the flour samples ranged from 0.42 g/ml to 0.67 g/ml packed bulk density; 0.39 g/ml to 0.47 g/ml loose bulk density; 0.88 ml/g to 2.10 ml/g oil absorption capacity; 1.50 ml/g to 3.90 ml/g water absorption capacity and 43.75% to 49.37% emulsion activity. The proximate composition of the bread samples ranged from 26.82% to 38.90% moisture, 4.23% to 5.10% fat, 6.10% to 9.25% protein, 1.90% to 2.45% ash, 0.12% to 0.64% crude fiber and 46.43% to 56.71% carbohydrate. The volume, weight and specific volume of loaves varied from 200 ml to 400 ml, 142.6 g to 170.2 g and 1.18 ml/g to 2.81 ml/g respectively. The crack formation of bread samples showed that there were no cracks on wheat bread (WF) and 25% yam flour substituted breads while 100 percent yam flour breads had large cracks. The sensory properties of the 25% yam flour substituted breads were statistically (p40.05) the same with the 100% wheat bread but differed from all the other bread samples. The mean score of the sensory attributes decreased as yam flour increased in the formulation. Sensory Evaluation of the bread samples showed that substitution level of 25% yam flour produced bread that was acceptable to the consumers whereas up to 50% and above were not acceptable. It is therefore recommended that substitution level of not more than 25% yam flour be used for yam/wheat composite bread production. & 2015 The Authors. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Chemical composition, physical and sensory properties of bread incorporated with raw and boiled African fan palm (Borassus aethiopum) root flours

“…The deleterious effects of addition of fiber on dough structure and loaf volume are due to the dilution of gluten which in affects gas retention (Shittu et al, 2007). The low specific volume of the 100% fan root bread may be attributed to its lack of gluten that is responsible for enhanced dough rise in leavened wheat flour bread (Amandikwa et al, 2015).…”

“…The score for texture (softness and chewiness) decreased with the level of root flour. The baking conditions (temperature and time), state of the bread components such as fibers, protein (gluten), starch (whether damaged or undamaged) and the amount of water absorbed during dough mixing, contribute to final texture of bread (Amandikwa et al, 2015). It has been used to enhance the strength of gluten, handling and baking properties of dough and gas retention by oxidation of -SH groups of gluten protein to -SS groups.…”

Quality and Storage Characteristics of Hot Press Tortilla Prepared from Yam-Wheat Composite Flour

“…Out of several methods under consideration, the production of tortillas from composite flour is a viable approach [1] [5], which is achieved by substitution of wheat flour with other flour to make healthier tortillas. Previous studies have shown that yam flours have higher mineral content, higher dietary fiber content, higher resistant starch content, and lower estimated glycemic index (eGI) than refined wheat flour [6] [7].…”

“…Some studies have been conducted on the use of wheat-yam composite flour for the production of bread, cake, and cookies [7] [17] [18]. However, there have not been any studies on the use of wheat-yam composite flours for the production of tortillas.…”

Evaluation of suitability of substituting wheat flour with sweet potato and tiger nut flours in bread making

“…Variations in water and oil absorption activity may be due to different protein concentration in wheat, sweet potato and tiger nut flours, their degree of interaction with water and oil and possibly the conformational characteristics. Water absorption capacity is important in dough consistency and baking quality of products (Amandikwa et al, 2015).…”