Abstract:
Bread is made mainly using wheat, substituting cassava for wheat is challenging due
to lack of a gluten network. Further the reduction of particle size affects the physicochemical
properties of flour, providing specific product features. Currently bread is
made incorporating only up to 30% of cassava. Hence, this study aimed to increase
the cassava substitution level by decreasing particle size. To reduce the particle size,
cassava was milled two (F2) and three times (F3) and their granular morphology,
particle size distribution, color, and functional properties, were determined. 30% of
cassava substituted bread was made using F2 and F3 and their characteristics were
compared. Using the best flour, treatment composites made as 30%, 40% and 50% of
cassava substitution levels, while 100% wheat bread was the control. Granular of F2 and
F3 were not damaged. Mean particle size of F2 and F3 was 150-180 µm. Particle size of
F3 greater than 180 µm was only 12.3%. In F2 it was 27.8%. There were no significant
differences (p > 0.05) in color, dispersibility, water and oil absorption capacities of both
flours. Swelling power, solubility index, bulk, and tapped densities were higher in F3
(5.83±0.20ab, 25.19±3.07a%, 0.4±0.00ab g/cm, 0.63±0.00ab g/cm) than F2 (5.46±0.30b,
13.81±2.77b%, 0.38±0.02b g/cm, 0.60±0.20b g/cm). Specific volume was higher in bread
made with F3 (2.41±0.07a ml/g) than F2 (2.22±0.06b ml/g). Crust color (L*) was
increased with F3 and specific volume was decreased. Hardness of dough was increased
with F3 and no significant difference in bread. Moisture, protein, fat, fiber, ash and
carbohydrate content of best product were 35.46±0.15a%, 7.00±0.00b%, 3.86±0.26a%,
0.78±0.03a%, 3.08±0.16a% and 53.10±0.38a% respectively. F3 was selected as the best
flour for bread making, and 40% of cassava substituted bread was selected as the best
product from seven-point hedonic tests. Particle size reduction helped to increase the
binding ability of cassava and increased substitution level up to 40%.
