الفهرس 
Material and methodsOnly 14 pages are availabe for public view
 |  | from | 122 |  |  |
| | | from | 122 | | |
Abstract
Two different dietary sources were used in this study. i..e, corn
cobs and carrot roots powders. The dietary sources were mixed with
~
wheat flour. (72%extraction) at different ratios (90 : 10 , ,
85 : 15 , 80 : 20 , and 75 : 25) the chemical properties, rheological
characteristics and the organoleptic properties for both the raw
materials and different mixtures were studied. The results can be
summerize in the following points :-
1.The chemical analysis :-
The chemical analysis of corn cobs, carrot roots powders, wheat
flour (72% ext.) and shorts showed that:
Ash content of, carrot roots powder were higher ( 11.4 % ) than
of corn cobs powder (2.450/0)while, it was about 0.46% in wheat flour
(720/0 ext.) and 3.850/0in shorts. Carrot roots powder have altitude ash
content (11.4%) which may be attributed to its high contents of
potassium (2.10/0), sodium (1.6%) calcium ( 0.42 ) , phosphorus
(0.340;0) and magnesium (0.170/0).
Crude protein of carrot roots powder and corn cobs powder
were 6.70/0and 4.620/0respectively compared to wheat Rour (720/0ext.)
9.840/0and shorts which have IS%
•
The starch contents of both cora cobs powder and carrot roots
powder were the some (8.12·/. aod 8.250/0 ) while wheat Dour
(728f.ext.) and shorts cootai- 83.SiIf. and 21.15·/. respectively ·
The phytate phosphorous was absent in both corn cobs and
carrot roots powders while wheat flour (72% ext.) had 0.08% and
shorts had 1.4% •
The beta carotene in carrot roots powder and coro cobs powder
were 36.66 ppm and 7.3 ppm respectively while wheat flour 72% ext.
bad 2.8 ppm.
The total dietary fiber contents in corn cobs and carrot roots
powder were 81.320/0 and 46..55% respectively while it was 2.8% in
wheat flour ( 72% ext. ) and 51 % in shorts ·
Soluble dietary fiber were 39.38% and 38.03% for corn cobs
powder and carrot roots powder respectively ..
Insoluble dietary fiber was high in corn cobs powder
( 41.940/0 ) and low in’ carrot roots powder ( 8.52,) •
i Results demonstrate that both corn cobs powder and carrot
roots powder have high contents of total pectic substances 35 ..38% and
34.530/0 respectively. It could be concluded that carrot roots powder
,
can use in high soluble dietary fiber bread making while corn cobs
powder can be use in the manufacture of high insoluble and soluble
dietary fiber bread ..
Concerning some choice minerals contents ; Fe, Cu , Zn , Mn
. .
and Pb found to be 280 ,32 , 85 , 178 and zero ( ppm) for com cobs
powder 0’ 423 , 37, 54 , 29 and zero ( ppm) for carrot roots powder,
18 , 21, 20 , 25 and zero ( ppm ) for wheat flour
( 72% ext. ) respectively ·
i ’
2. Chemical analysis of balady bread manufactured from corn cobs
and carrot roots powders :-
Results showed tbat addition of corn cobs or carrot roots
powders in replacement rates 10 , 15 , 20, and 25% of wheat flour
(72% ext.) increased the dietary fiber contents ash and reduced
sugars in all rates wbiledecreased starch, craude protein, ether extract
and phytate content.
3. The rheological properties :-
3.1. Farinogram properties :-
The results showed tbat addition of corn cobs powder at
replacement ratios 10 , 15 , 20 and 25% to wheat flour (72% ext. )
increased water absorption which may be due to the strong water
binding ability of fiber . Also the arrival time increased at all levels
except at level of 10%
•
The results showed that addition of carrot roots powder
increased water absorption while the arrival time decreased at 100;0
”
and 150/0 replacement and increased gradually at levels 20% and 25%
also dough development time increased and dough stability increased
at all ratios of addition ·
3.2. Extensogram properties :-
The addition of corn cobs powder at rates 10,15,20 and 25%
replacement of flour (72% ext.) decreased dough extensibility and
dough energy wbile resistance to extension increased it could be
concluded that cora cobs powder addition weaked the dough
properties .
The addition of carrot roots powder at the abovementioned
ratios gradually decreased dough extensibility and dough energy.
Addition of carrot roots powder showed increasment in resistance to
extension.
4. Organaleptic evaluation :-
The results showed that balady bread supplemented with 10
%
corn cobs powder showed no difference in crust color, aroma, Taste,
Texture and overall acceptability compared with control. Gradual
reduction was noticed in all the parameters as the ratios of corn cobs
powder increase.
About balady bread supplemented with 15,20, and 25% carrot
roots powder showed lowest values in all parameters compared with
control.
The organoleptic properties of toast bread producing by mixing
wheat flour (720/oext.) with different ratio of corn cobs and carrot
roots powder showed gradual reduction in its volume by increasing
replacing ratios.
5. Improvement of high fiber bread:-
L-ascorbic acid was added with different ratios SO, 75, 100, 125
and 150 p.p.m. to high fiber bread mixture containing 15°/0 corn cobs
powder or carrot roots powder aDd 8S·/. wheat Oour(72°/o ext.).
The results showed an improvement in both rheological and
organoliptic properties especially at 100 p.p.rn of ascorbic acid in
balady bread and Toast bread.
from the results it could be concluded that corn cobs powder
and carrot roots powder could use in manufacture of high,tiber bread
with less phytate with higher iron contents than shorts bread.