Abstract:
This study was carried out to test the effect of adding faba bean and
cowpea flours to wheat flour on the quality of dough and bread. Wheat
flour in standard bread formulation was replaced with dehulled faba bean
and cowpea flours before and after germination at levels of 5, 10 and 15%
(wt/wt).
Samples of wheat, cowpea and faba bean were analyzed for ash,
moisture, fat and protein. Moisture content was 13.68, 7.33, and 9.26%,
ash content was 0.55, 2.81 and 3.03%, protein content was 11.47, 28.03
and 23.01% and the fat content was 2.35, 1.53 and 1.57%, for wheat, faba
bean and cowpea flours, respectively.
Amino acids profile was studied for wheat flour, faba bean and
cowpea (before and after germination), germination has lowered the
levels of all amino acids except glutamtic acid which increased in both
faba bean and cowpea. Also, serine and aspartic acids have been
increased in faba bean after germination. In cowpea lysine has increased.
Wheat flour and composite flours were tested for gluten quality and
quantity. while falling number, farinograph and extensograph
characteristics were determined.
Specific volume and sensory evaluation tests were conducted on
bread made from composite flours.
Falling number showed a significant (P≤0.05) decrease with
increase of germinated cowpea and faba bean flours from 489 sec. in
control sample to 243 sec. in 15% germinated faba bean flour and 206
sec. with 15% germinated cowpea flour.
Generally, addition of cowpea and faba bean flours to wheat flour
increased water absorption, development time and degree of softening,
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while the stability of dough was decreased. Adding faba bean and cowpea
to wheat flour decreased the energy, extensibility and maximum
resistance of wheat flour and increased its resistance to extension and
ratio number.
Bread with 5% germinated faba bean or cowpea flours gave the
highest specific volume (3.70 and 3.73 g/100 g, respectively) of bread
loaf and gained the highest score of general acceptance.
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