Effect of optimizing process variables on the quality characteristics of cassava-wheat composite bread

The optimisation of bread-making process can have a positive impact in ramping up the quality characteristics of cassava-wheat bread to that of whole wheat bread. In this study, a threevariable Box-Behnken design response surface methodology was employed to investigate and optimise independent variables namely cassava flour composition, water content and proofing time in relation to response variables namely dough yield, loaf specific volume and loaf protein of cassava-wheat-composite bread. The data from the experimental design were fitted into second-order regression models and their validity and reliability were confirmed by analysis of variance. Optimal cassava flour composition, water content and proofing time were derived as; 100 g/kg, 589 g/kg and 90 min, respectively. It was revealed that cassava flour composition had the most effect on the quality characteristics of cassava-wheat-composite bread. At constant cassava flour composition, increase in water content and proofing time had a positive effect on all the studied quality characteristics of cassava-wheat composite bread. Increase cassava flour composition regardless of proofing time and water content had a negative effect on loaf specific volume and protein. This study has provided bread-making conditions which can be utilised in enhancing the consumer acceptability of cassava-wheat composite bread.

Proximate and Sensory Properties of Wheat-Cocoyam (Colocasia Esculenta) Composite Bread

In this study, samples of composite breads were produced from wheat and cocoyam flour blends using D-optimal design mixture, in the following proportions: 95:5, 90:10, 85:15. Bread sample which contained 100% wheat flour was also produced and this served as the control. The bread samples obtained were subjected to proximate and sensory analysis. The following results were obtained for the whole wheat flour bread: moisture (27.65%), protein (11.33%), crude fibre (0.59%), ash content (0.78%, fat (8.19%) and carbohydrate content (53.69%), respectively. While the composite bread samples had the moisture, protein, crude, ash, fat and carbohydrate in the following ranges:17.93-23.63%, 7.16-10.83%, 0.59-0.88%, 0.47-0.98%, 4.43-7.81% and 55.94-1.31%, respectively. The sensory tests carried out on the bread samples indicated that there was no significant difference between the whole wheat bread and the composite bread samples for flavour, crumb appearance and taste. However, for texture, overall preference and crust colour properties of the bread samples, significant differences were observed. From the study, it can be concluded that wheat flour can be substituted with cocoyam flour and bread samples made from this combination (up to 15% cocoyam flour inclusion) were acceptable. It was observed that the 100% wheat flour bread is the most acceptable, followed by the 5% cocoyam flour composite bread samples. Usage of cocoyam flours in bread baking can contribute significantly to enhancing nutrition and curbing the rising cost of bread.

FORMULATION OF GLUTEN-FREE BREAD WITH DIFFERENT LEVELS OF HYDROXYPROPYL METHYLCELLULOSE, RAW BANANA FLOUR AND PROOF TIME: MODELLING, PROXIMATE AND SENSORY ANALYSES

Semi-urbanization has increased the demand of bakery products triggering variousgluten-related disorders including Celiac Disease (CD), Non-celiac Gluten Sensitivity (NCGS), Gluten Ataxia and Wheat Allergy. Among these, CD accounts for nearly 1-2%global population. Gluten withdrawal- cornerstone treatment for CD is a bumpy road with nutritional deficiencies and poor quality of life. Additionally, there is a surge of people intentionally avoiding gluten for various reasons. The present work intends to optimize a formula for a gluten free (GF) bread and determine the effect of prooftime, hydroxypropyl methylcellulose (HPMC) and raw banana flour at different levels on moisture content, bake loss, specific volume, texture parameters andcrust-crumb brightness (L*) using response surface methodology (RSM) based on central composite rotatable design (CCRD).The results revealed moisture content, hardness, springiness, resilience and crust-crumb L*were significantly affected. Different proof time levels altered moisture content, bake loss and colour parameters with no influence on textural parameters. Increasing levels of HPMC impeded bake loss and crumb lightness but exacerbated hardness. Nonetheless, on its interaction with raw banana flour, there was antagonistic effect on hardness. Addition of raw banana flour darkened the bread. Thus, optimal conditions (HPMC 2%, raw banana flour 37.16% and proof time 40mins) were appliedto produce good quality bread. Furthermore, sensory and proximateanalyses of optimum GF bread were compared to whole wheat bread depicting higherprotein-fat content, lower carbohydrate content and overall acceptability score of 7.88for the former; the demand for which is steadily and incessantly expanding