الفهرس 
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Abstract
The problem at hand was carried out to study possibility of partial
supplementation of wheat flour (72% extraction) with barley, corn flours at
levels of 10, 15 & 20% and defatted soy flour at levels of 5, 7.5 & 10%.
Rheological properties, chemical composition and organolyptic evaluation
of pan bread were determined. The obtained results were summarized as
follows:
1- Chemical composition of wheat, barley, com and defatted soy
flours:
The chemical analysis showed that wheat flour (72% extraction)
contained 11.20% moisture, 9.83% protein, 1.09% fat, 2.58% fiber, 0.51%
ash, 0.79% reducing sugars and 1.090/0non-reducing sugars. Barley flour
contained 11.90% moisture, 10.89 % protein, 2.12% fat, 4.68% fiber,
2.80% ash, 0.49% reducing sugars and 2.19% no-reducing sugars. Corn
flour contained 10.400/0 moisture, 9.19% protein, 3.50% fat, 2.50 fiber,
1.55 ash, 0.670/0reducing sugars and 2.69% non-reducing sugars. Defatted
soy flour contained 10.20% moisture, 48.05% protein, 2.90% fat, 5.83%
fiber, 3.71% ash, 1.95% reducing sugars and 3.94% non -reducing sugars.
2- Rheological properties :
2.1. Farinograph test:
2.1.1. Wheat and barley fl.ours blends:
The results showed an increase in the water absorption and arrival
time with increasing the addition of barley flour. The dough development
time no changed between control and addition of 10% barley flour, while
addition of 15 and 20% barley flour lead to increase dough development
time compared with control. The dough weakening increased with
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increasing the addition of barley flour. Dough stability decreased with
increasing the addition of barley flour may be attributed to the barley flour
have less gluten for dough.
2.1.2. Wheat and com flours blends:
The results showed decrease in the water absorption with increasing
the addition of corn flour. This was explained to be a result of the larger
granules of com flour. Arrival time decreased with increasing the addition
of corn flour. Dough development time no changed between control and
addition of 10% com flour, while addition of 15 and 20% com flour lead
to increase dough development time. These increase may be due to the
difference in granularity of com flour. Dough stability decreased with
increasing the addition of com flour. These decrease because of the polar
points of contact might be few and weakened the gluten network. Dough
weakening increased with increasing the addition of com flour as a result
of the breakdown of gluten network after elapsing at the appropriate
mixing time.
2.1.3. Wheat and defatted soy flours blends:
The results showed an increase in the water absorption with
increasing the addition of defatted soy flour. These increasing was
explained to be due to the increase of protein in the dough. Arrival time
increased with increasing the addition of defatted soy flour. Dough
development time no changed between control and addition of 5% defatted
soy flour, while addition of 7.5 and 10% defatted soy flour lead to increase
dough development time. Dough stability decreased with increasing the
addition of defatted soy flour. These decreasing may be attributed to the
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___ ----------SUMMARy ANDCONCLUSION- -91-
decrease in gluten content of the mixtures.Dough weakening increased
with increasing the addition of defatted soy flour.
2.2. Extensograph test:
2.2.1. Wheat and barley flours blends:
The results indicated that dough extensibility, resistance to
extension, proportional number and dough energy decreased with
increasing the addition of barley flour. These decrease may be attributed to
the barley flour contain more reducing agents and absence gluten moreover
protease which weaken dough structure.
2.2.2. Wheat and corn flours blends:
The results indicated that dough extensibility, resistance to
extension, proportional number and dough energy decreased with
increasing the addition of com flour. These decrease in dough extensibility
may be due to the deficiency of com flour protein in gliadin which is
responsible for this property, while decrease resistance to extension and
dough energy are believed to be due to the deficiency of com protein in
glutenin.
2.2.3. Wheat and defatted soy flours blends:
The results indicated that dough extensibility and dough energy
decreased with increasing the addition of defatted soy flour. Resistance to
extension and proportional number increased with increasing the addition
of defatted soy flour.
______________ SUMMARy AND CONCLUSION- -92-
3- Chemical composition of pan bread:
3.1. Pan bread supplemented with 10, 15 and 20% barley flour:
The results indicated that moisture, protein, fat, fiber, ash, reducing
sugars and non-reducing sugars contents increased with increasing the
addition of barley flour.
3.2. Pan bread supplemented with 10,15 and 20% corn flour:
The results indicated that moisture content decreased with
increasing the addition of com flour because of high fat content of corn
flour may be reduce water holding capacity too. The protein content
decreased with increasing the addition of com flour because of low protein
content in com flour, while fat, fiber, ash, reducing sugars and nonreducing
sugars increased with increasing the addition of com flour.
3.3. Pan bread supplemented with 5, 7.5 and 100/0 defatted soy flour:
The results indicated that moisture, protein, fat, fiber, ash, reducing
sugars and non-reducing sugars contents increased, with increasing the
addition of defatted soy flour.
4- Amino acids profiles of pan bread:
4.1. Amino acids profile of pan bread supplemented with 10% barley
flour:
The results indicated an increase ten amino acids which were
isoleucine, leucine, phenylalanine, valine, histidine, aspartic acid, tyrosine,
serine, proline and alanine. On the contrary, decreased seven amino acids
which were lysine, threonine, methionine, tryptophane, cystine, arginine
and glutamic acid compared with control. On the other hand, glycine was
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_____________ SUMMARy AND CONCLUSION- -93-
equal between pan bread (control) and pan bread supplemented with 10%
barley ’flour.
4.2. Amino acids profile of pan bread supplemented with 10% com
flour:
The results indicated an increase ten amino acids which were
isoleucine, leucine, phenylalanine, valine, histidine, aspartic acid, tyrosine.
serine. proline and alanine. On the contrary, decreased eight amino acids
which were lysine, threonine, methionine, tryptophane, cystine. arginine.
glutamic acid and glycine compared with control.
4.3. Amino acids profile of pan bread supplemented with 50/0 defatted
soy flour:
The results indicated an increase twelve amino acids which were
isoleucine, leucine, lysine, phenylalanine, threonine, valine, tryptophane,
aspartic acid, tyrosine, serine, proline and alanine. On the contrary,
decreased six amino acids compared with control which were methionine,
cystine, histidine, arginine, glutamic acid and glycine. These decreased of
amino acids in all samples may be caused chemical reaction between
amino acids and reducing sugars (Maillard reaction). Moreover yeast
additive which consume amino acids during fermentation,
5- Chemical score :
The results showed that lysine was the first limiting amino acid in
both pan bread (control) and pan bread supplemented with 10% barley
flour. Tryptophane was the first limiting amino acid in pan bread
supplemented with 10% com flour. Methionine was the first limiting
amino acid in pan bread supplemented with 5% defatted soy flour.
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____________ -SUMMARy AND CONCLUSION- -94-
6- Baking quality of pan bread products by using different recipes:
6.1. pan bread supplemented with 10, 15 and 20% barley flour:
The results indicated that the loaf weight increased because of
barley flour caused increase in water absorption of the recipes. On the
contrary, the loaf volume and specific loaf volume decreased with
increasing addition of barley flour because of the lack of gluten of the
barley proteins.
6.2. Pan bread supplemented with 10, 15 and 20% corn flour:
the results indicated that the loaf weight, loaf volume and specific
loaf volume decreased with increasing addition of com flour because the
amount of the water absorption was considered as a limited factor for
controling the loaf weight, while the quantity and quality of proteins were
the main factor of weakening of gluten, consequently loaf volume and
specific loaf volume decreased.
6.3. Pan bread supplemented with 5, 7.5 and 10% defatted soy flour:
The results indicated that the loaf weight increased. On the other
hand, when addition of 5% defatted soy flour no changed loaf volume
compared with control, but addition of 7.5 and 10% defatted soy flour lead
to decrease loaf. volume. Respecting specific loaf volume decreased with
increasing addition of defatted soy flour because of weakening of the
resulted dough that can not captured the fermentation gases.
7- Organolyptic evaluation of pan bread:
7.1. Pan bread supplemented with 10, 15 and 20% barley flour r
The statistical analysis showed that pan bread supplemented with
100/0barley flour there was no significancedifference in crust color, crumb
_____________ SUMMARYAHDCONCLUSION- -95-
uniformity, crumb color, taste, odor andoverall acceptability compared
with control. Pan bread supplemented with 15 and 20% barley flour there
was significance difference in crust color, crumb color, taste, odor and
overall acceptability compared with control. Pan bread supplemented with
15% barley flour there was significance difference in crumb uniformity
compared with pan bread supplemented with 20% barley flour.
7.2. Pan bread supplemented with 10,15 and 20°;” corn flour:
The statistical analysis showed that pan bread supplemented with
10% com flour there was no significance difference in crust color, crumb
uniformity, crumb color, taste, odor and overall acceptability compared
with control. Pan bread supplemented with 15 and 20% com flour there
was significance difference in crust color, crumb color, taste, odor and
overall acceptability compared with control. Pan bread supplemented with
15% com flour there was significance difference in crumb uniformity
compared with pan bread supplemented with 20% com flour.
7.3. Pan bread supplemented with 5, 7.5 and 100/0defatted soy flour:
The statistical analysis showed that pan bread supplemented with 5,
7.5 and 10% defatted soy flour there was no significance difference in
crust color and crumb color compared with control, while pan bread
supplemented with 5 and 7.5% defatted soy flour there was no significance
difference in crumb uniformity, taste, odor and overall acceptability
compared with control. Pan bread supplemented with 10% there was
significance difference in crumb uniformity, taste, odor and overall
acceptability compared with control.
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_____________ SUMMARy AND CONCLUSION- -96-
In a conclusion, it is suggested that the supplementation of wheat
flour (72% extraction) with barley, corn and defatted soy flours are
technologically, feasible and nutritionally advisable. Therefore, we
recommend that pan bread can be successfully produced by replacing
barley flour at level of 10%. As well as, corn flour at level of 10%, while
defatted soy flour at levels of 5 and 7.5%.
As well as, the problem at hand was carried out to study possibility
of partial enrichment of wheat flour (82% extraction) with ferrous sulphate
at levels of 0.02,0.03 & 0.05% and zinc sulphate at levels of 0.01, 0.015
& 0.020/0. Rheological properties, chemical composition and organolyptic
evaluation of balady bread were determined. The obtained results were
summarized as follows :
1- Chemical composition of unfortified wheat flour (82% extraction)
and balady bread (control):
The chemical analysis of wheat flour (82% extraction) and balady
bread (control) showed the following composition respectively : moisture
12.33 & 34.200/0,protein 10.57 & 10.63%, fat 1.89 & 1.90%, fiber 2.60 &
3.39%, ash 1.20 & 2.200/0, reducing sugars 0.88 & 1.70% and nonreducing
sugars 1.19 & 0.85%.
2- Rheological properties :
2.1. Farinograph test:
2.1.1. Wheat flour and ferrous sulphate blends:
Addition of ferrous sulphate to wheat flour at levels of 0.02, 0.03
and 0.05% lead to water absorption recorded (60.2, 60.5 and 60.7%)
respectively, while control recorded (60%). Arrival time recorded (2,2.25
____________ SUMMARy AND CONCLUS/ON- -97-
and 2.50 min.) respectively, while control recorded (2min.). Dough
development time recorded (4.25~4 and 4min.) respectively~while control
recorded (4min.). Dough stability recorded (8, 8 and 7.75 min.)
respectively, while control recorded (8 min.). Dough weakening recorded
(80~80 and 85 B.D.) respectively, while control recorded (80 B.D).
2.1.2. Wheat flour and zinc sulphate blends:
Addition of zinc sulphate to wheat flour at levels of 0.01, 0.015 and
0.02% lead to water absorption recorded (60.1~ 60.3 and 60.5%)
respectively, while control recorded (60%). Arrival time recorded (2,2 and
2.25 min.) respectively, while control recorded (2 min.).Dough
development time recorded (4, 4.25 and 4.25 min.) respectively, while
control recorded (4 min.). Dough stability recorded (8,8 and 8.25 min.)
respectively, while control recorded (8 min.). Dough weakening recorded
(80,80 and 80 B.D.) respectively, while control recorded (80 B.D.).
2.2. Extensograph test:
2.2.1. Wheat flour and ferrous sulphate blends:
Addition of ferrous sulphate to wheat flour at levels of 0.02. 0.03
and 0.05% lead to dough extensibilityrecorded (1I0, 105 and 103mm.)
respectively, while control recorded (110 mm.). Resistance to extension
recorded (330, 325 and 325 B.D.) respectively, while control recorded
(330 B.D.), consequently proportional nwnber (R/E) recorded (3,3.09 and
3.15) respectively, while control recorded (3). Dough energy recorded
(46.0,45.8 and 45.5 em’) respectively, while control recorded (46.1 em’).
_____________ SUMMARy AND CONCLUSION- -98-
2.2.2. Wheat flour and zinc sulphate blends:
Addition of zinc sulphate to wheat flour at levels of 0.01, 0.015 and
0.02% lead to dough extensibility recorded (110, 108 and 106 mm.)
respectively, while control recorded (110 mm.). Resistance to extension
recorded (330, 330 and 325 B.D.) respectively, while control recorded
(330 B.D.), consequently proportional number (RJE) recorded (3,3.05 and
3.06) respectively, while control recorded (3). Dough energy recorded
(46.1, 46.0 and 45.9 cnr’) respectively, while control recorded (46.1 crrr).
3- Iron contents of wheat flour and balady bread samples:
The results showed that iron contents of wheat flour were 10.96 and
11.36 (mg/IOO gm) in balady bread (control). This increasing may be due
to the addition of bran during preparation of bread which is known to be
rich in iron. Iron content increased gradually to 15.85,20.83 and 25.53
(mg/IOOgm) when ferrous sulphate was added at levels of 0.02, 0.03 and
0.05% respectively.
4- Zinc contents of wheat flour and balady bread samples :
The results showed that zinc contents of wheat flour were 2.59 and
2.79 (mg/IOOgm) in balady bread (control). This increasing could be due
to the presence of bran coating the loaves bottom in balady bread. Zinc
content increased gradually to 4.82,6.11 and 8.75 (mg/l00gm) when zinc
sulphate was added at levels of 0.01, 0.015 and 0.02% respectively.
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____________ -SUMMARy ANDCONCLUSION- -99-
5- Organolyptic evaluation of balady bread :
5.1. Balady bread enrichment with 0.02, 0.03 and 0.05 ferrous
sulphate:
The statistical analysis showed that there was no significance
difference in separation of layers, roundness, crust color, crumb color,
distribution of crumb, taste and odor between balady bread (control) and
balady bread enrichment with 0.02,0.03 and 0.05% ferrous sulphate.
5.2. Balady bread enrichment with 0.01, 0.015 and 0.020/0zinc
sulphate:
The statistical analysis showed that there was no significance
difference in separation of layers, roundness, crust color, crumb color,
distribution of crumb, taste and odor between balady bread (control) and
balady bread enrichment with 0.01, 0.015 and 0.02% zinc sulphate.
The above mentioned results indicated that the results enriched
balady bread with iron and zinc may be used to solve some problems of
malnutrition as anemia and dwarfism. These results may be help in
preparation some diets to certain groups of laborious.