الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 144 |  |  |
| | | from | 144 | | |
Abstract
SUMMARY
Soybeans is one of the most important crops for humman feeding as
it contains a high protein content which accounts for about 35 - 38%.
Soymilk represents an inexpensive and aboundant source of good protein
quality, that could be the best choice to replace or extended the dairy
products, to reduce their price and achieve the nutritions and healthy
properties.
The aim of the present work was to study the posibility of using
soymilk for OF Feta-like cheese making from a mixture of milk and
soymilk in rate of 2: 1, with the using of starter culture from 1 to 3%
containing 25% or 50% probiotic bacteria (Bijidobacterium locus Bb 12).
The produced cheeses were more acceptable than the control either
that made from milk or from soy milk and more effective in lowering the
total cholesterol, LDL-cholesterol and triglycerides.
The results of our investigation have been presented and discussed in
two main parts as follows:
Part 1:
Section 1: Preparation and chemical properties of soymilk
In this section, the soymilk was prepared from soybean seeds and the
chemical composition was studied. The obtained results cleared that:
1- preparation of soymilk reduced the antinutrational factors of soybean
and soymilk like, trypsin inhibator, phytic acid and urease activity.
2- A slight increase in protein, ash and fat%. Also, a slight decrease was
recorded in moisture, fibers and carbohydrates%.
3- The mixture of milk and soymilk with ratio of 2: 1 reflect a slight
increase in protein and carbohydrate, however a slight decrease was
noticed in moisture,ash, and fat compared with milk.
Summary 128
Section 2: Production and properties of probiotic OF Fetalike
cheese made from mixture of milk and
soymilk (2: 1).
In this section the mixture of milk and soymilk 2:1 was concentrated
by ultrafiltration technique up to -28% total solids. The final concentrate
was then heated to 75°C for 2 min., cooled to 40°C and then devided into
two parts. The first one was treated with 1,2 and 3% mixed starter
containig 50% Bifidobacterium lactis Bb12 + 50% Lb. casei sub spp.
casei + L. lactis sub spp. lactis + L. lac tis sub spp. cremoris (1:1:1).
The second part was treated with 1,2 and 3% mixed starter
containing 25% Bifidobacterium lactis Bb12 + 75% Lb. casei sub sub
spp. casei + L. lactis sub spp. lactis + L. lactis sub spp. cremoris (1:1:1).
The control cheese of soymilk or whole milk were only treated with
I% mixed starter containing Lb. casei sub spp. casei + L. lactis sub spp.
lactis + L. lactis sub spp. cremoris (1:1:1) without Bifidobacterium.
The cheese of different treatments were made as described under
materials and methods and were analyzed when fresh and after 15 days
intervals up to 45 days for organoleptic, chemical and microbiological
properties.
The obtained results can be summarized as follows:
1. The chemical composition, namely, moisture, fat, salt and total
nitrogen contents of all cheese samples were not significantly affected
for different treatments and the slight effect was due to the lowering of
moisture content.
2. The moisture content of all cheese treatments were gradually decrased
all over the storage period. The acidity was gradually increased by
advancing the storage. The acid development was proportional to the
percentages of the added starter to retentate during cheese preparation.
129 Summary
On the other hand. T3 and T6 recorded the highest acidity during the
storage.
3. The ripening indices of the cheese samples showed that the protein
and fat breakdown were proportional to the percentages of starters
added containing 50% Bifidobacterium lactis BbI2. The increase of
soluble nitrogen, SN/TN, soluble tyrosein, tryptophan and total
volatile fatty acids indicating an increase of ripening during storage.
Treatment 3 and 6 (treated with 3% starter of 50% or 25%
Bifidobacterium lactis BbI2 + 50% or 75% mixed lactic starter
respectively) recorded the highest ripening indices compared with the
control.
4. The sensory evaluation for the produced cheese showed that treatment
3 and 6were the best treatments. This was a reflection of the mixing of
both soymilk and Bifidobacterium lactis BbI2.
5. The firmness of all cheeses were increased gradually by increasing the
storage period in all treatments compared with soy cheese (control T8).
6. The microbiological examination of all cheese samples recorded an
increase of total bacteria count, lipolytic bacteria, protyoletic bacterial
and Bifidobacteria count at the beginning of the storage period
compared with control treatments. At the end of storage their was a
gradual decrease. The coliforms were not detected all over the storage
period in all treatments. The mould and yeasts were absent at the
beginning and till 15 days of storage however they were detected at
the end of the storage period.
Summary 130
Part II:
Section 1: The Hypocholesterolemic effect of the probiotic
and UF Feta-like cheese on rats fed on
cholesterol enriched diet:
This part of the study aimed to explore some of the health promoting
effect of probiotic UF Feta - like cheese with regard to their potential role
in lowing the cholesterol by feeding the rats on cholesterol-enriched diet
containing probiotic UF soy Feta - like cheese.
The results could be summarized as follow:
1) The beginning period of feeding showed a significant differances
between negative group and other groups in total cholesterol level,
triglycerides, HDL-cholesterol and VLDL + LDL -cholesterol levels .
2) The groups of rats which fed on T3 and T6 recorded the highest lowring
in total cholesterol level .
3) The triglyceride level showed a significant defferance of decrerase in all
groups ofUF Feta-like cheese and the lowest level recroded in T3 .
4) The HDL-cholesterollevel decreased up to the end of the forth week all
of groups fed on UF Feta-like cheese treatment, but at the end of 6
weeks the level ofHDL-cholesterol increased.
5) The (VLDL+ LDL)-cholesterollevel gradually increased up to 4 weeks
then it decreased at the end of 6 weeks which recorded the lowest level
compared with its content at the first week.
131 Summary
Section 2: Histopathological profile of rats fed on
cholesterol-enriched diet as a functional of
probitic OF feta-like cheese:
• Group (1) : Fed on basal diet (negative control). The organs showed
no significant changes.
• Group (2) : Fed on basal diet + 0.5% cholesterol (positive control)
Kidney, liver and heart had a degenerative changes in the reval tissues.
Cloudy swelling in the tubular epithlium which showed intracytoplasmic
and some glomurli fregmentation of the tuft and replaced by basophilic
calafied mass, degenerative changes in the hepotocytes include vacular &
hydrobicdegeneration with pole acidophilic. Cutoplasm and Hyaline
degredation in the cardiac muscles, intermuscular hemorrhage were
recorded in the blood vessels respectively.
• Group 3 - 8 (treated groups): Fed on 0.5% cholesterol + deferent
treatments from 3 to 8 supplemented with (10% casein, 10% fat)
basal diet:
• Some histopathological changes were recorded in the reual tissue of
the kidney include, cloudy swelling in the reual epthelium, with
intracytoplasmic eosiuphilic granules with storshape lumen. In the
liver mild degeneration changes in the pareuchyma in the forum of
hydrobic degeneration with pyknotic nuclei, congestion in the portal
bloodvessels with mild mononuclear cellulor infiltration. But non
significant changes were recorded in the heart.
• Group 9: Fed on 0.5% cholesterol + treatment 7 supplemented with
(10% casein, 10%fat) basal diet:
Mild degenerative changes in the forum eosinophilic substance in the
lumen of the tubules of kidney, also some of the loumurli showed
destruction and others showed shrinkage. In the liver, the hepatocytes
Summary 132
showed vacuo lotion & the central vein showed diltation. But the cardioc
muscle of heart showed non-significant histopathological changes.
• Group 10: Fed on 0.5% colesterol + treatment 8 supplemented with
(10% casein, 10 % fat) basal diet: the histopathological changes of
kidney were mild, only represented by desauamation of the liuing
epithdium of the reual tubules with some destruction of few
glomurli. The degenerative changes of liver were present as that of
previous group, only a new finding represented by severe congestion
of the blood vessels. Finly mild intermuscular edema of heart, also
intermuscular cangestion of some blood vessel were recorded in
same microscopic observation.
from the preivious study it could be concluded that
• Prepared soy milk by previous described method to obtained soy
milk with good quality and characteristics.
• Soy milk can be used with milk up to 28% total solids in making
UF Feta-like cheese without any affects on the cheese characteristics
which supplemented with Bifidobacterium lactis Bb 12 + Lactic
culture (Lb. casei sub spp. casei + L. lactis sub spp. lactis + L.
lactis sub spp. cremoris 1: 1: 1) at ratio of 3%
• Producing UF Feta-like cheese from healthy propertries by adding
3% from starter culture containing 50% Bifidobacterium lactis Bb
12 + 50% Lactic culture (Lb. casei sub spp. casei + L. lac tis sub
spp. lactis + L. lactis sub spp. cremoris 1: 1: 1).
• The produced cheese lowerd the serum of total cholesterol level in
the rats blood which fed on cholesterol-enriched diet.