الفهرس 
NTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
he application of nanotechnology plays an important role in the
field of food processing because of its positive role on functional and
technological characteristics of the products.
So, this study aimed to produce soy protein isolate and glycinin
nanoparticles using High Intensity Ultrasonic, characterization of the
obtained nanoparticles by (TEM, FTIR, Zeta potential, XRD and particle
size distribution), determination of functional properties (water holding
capacity, oil holding capacity, emulsifiying properties and protein
solubility) for the obtained proteins.
The obtained soy protein particles were used for production of
food products such as beef burger, mayonnaise and apple chips and
studying the functional characteristics of these products during the storage
period.
The obtained results of this study are summarized in the following
points
Part I: Extraction of soy protien and glycinin
Soy protein isolates (SPI) and glycinin (GLY) protein was
extracted by aqueous solutions of adjusted pH-values. Results obtained
for the chemical composition of protein isolate showed that the protein
content in the soybean protein isolate was 90.4 % while in glycinin 91.3
%. There was also a significant difference between all the other
parameters, moisture content, Fat and Ash content of the obtained
fractions.
Part II: Preparation and characterization of nanoparticles
Application of high intensity ultrasonic (400 W for 50 min)
reduced particle size of soybean protein isolate from 123.9 nanometers to
about 63.09 nanometers. The use of ultrasonication with the glycinin
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SUMMARY
Dina, E. H. Azab (2019), Ph.D., Fac. Agric., Ain Shams Univ.
protein led to the synthesis of aggregated glycinin protein molecules from
the size of 85 nanometers to a glycinin protein of 223 nanometers.
FTIR for soybean protein and nano soybean protein showed an
increase in the intensity of active groups at wavelengths (1000-2000cm-1),
which is the finger print area of protein. This indicates that cracking large
molecules into nanometer particles has increased the effective groups on
the surface of molecules. As a result of increased surface area of the part
for nano glycinin from glycinin, the intensity of active groups increased
slightly due to the aggregation of molecules.
The results of particle size distribution showed a poly dispersion
index of soybean protein isolate, nano soy protein, glycinin and nano
glycinin of 0.462, 0.414, 0.79 and 0.567, respectively.
The conversion of protein molecules from their natural size to the
nanometer size had an effect on the protein’s hydrophobicity, which
increased in the soybean protein from 75.2 to 87.9 degrees. In glycinin,
the results for hydrophobicity increased from 18.5 to 72.3°.
Zeta potential showed a difference in the charge on soybean protein
molecules after treatment with ultrasonication, Zeta potential values of
soy protein was (-27.3), while it was increased to (-34.3) for nano
soybean protein. In the case of glycinin there was a slight increase in the
charge, where it was - 25.1 for glycinin and -25.5 in the protein glycinin
nanometer.
There were significant differences in both WHC and OHC for
nano soy protein and nano glycinin compared with soybean protein and
glycinin. The water holding capacity of the tested proteins were 2.70,
5.79, 2.28 and 4.03 (g/g), respectively for SPI, NSPI, GLY and NGLY.
There were significant differences in the solubility between the
soybean protein isolate and the soybean protein in nanoscale .This is due
to improved protein solubility due to the decrease in the size of the
protein molecules and the increase in the surface area, as well as in the
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SUMMARY
Dina, E. H. Azab (2019), Ph.D., Fac. Agric., Ain Shams Univ.
solubility between glycinin and nano glycinin protein at different pH
degrees (7, 9 and 11).
X-ray diffraction showed a slight deviation at the top of the curve
and a decrease of 2θ from 20.87 to 19.81 to the left, which in turn
indicated a decrease in the crystallization of the nano soy protein from the
soybean protein isolate. In the nano glycinin protein, there was right shift
in curve and increase of 2θ from 19.75 to 19.93. This indicates an
increase in the degree of crystallization.
Part III: Application of nano proteins in some foods
Production of burger
Effect of freezing storage on moisture content of burger samples
There was a decrease in moisture content of the negative control
sample. The moisture losses percentage in frozen burger samples were
2.64%, 1.89%, 1.07 %, 1.46 % and 0.92% for negative control and those
samples supplemented with SPI, NSPI, GLY and NGLY, respectively.
Effect of freezing storage on protein content of burger samples
The protein content of burger samples decreased as the time of
frozen storage increased. The percentage loss was the lowest for NGLY
samples (1.16%) and the highest loss was for the negative control (6. 5%).
This indicated that nano soy protein particles improved the binding effect
of water molecules, as well as their protecting effect on protein during
freezing storage.
Quality characteristics and cooking measurements of burger
pH measurement of burger samples
There was a decrease in pH at the end of frozen storage. The
negative control decreased slightly from (5.9 to 5.8), SPI (6.5 to 6.4) and
GLY (6.6 to 6.5). There were no changes in pH for NSPI and NGLY
burgers. These results may be due to the ability of nano soy protein to
bind water. The decrease in pH during frozen storage may be led to the
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SUMMARY
Dina, E. H. Azab (2019), Ph.D., Fac. Agric., Ain Shams Univ.
breakdown of glycogen and accumulation of lactic acid during frozen
storage.
Shrinkage percent of cooked burger samples
The lowest shrinkage percent at zero time was for NSPI and
NGLY burgers (16.82 and 17.53), respectively. In addition, the shrinkage
percent was increased during frozen storage for all burger samples.
However the increase in the shrinkage percent was lowest in NSPI and
NGLY burger samples.
Cooking loss and cooking yield of cooked burger
There was a significant difference (at p ≤ 0.05) in the percent of
cooking yield and cooking loss of burger samples among the treatments.
The addition of soy proteins either in the form of raw or nano proteins led
to an increase in moisture retention. During the storage period, there was
an increase in the percentage of cooking loss as a result of the freezing,
which lead to the formation of ice crystals in the burger and also reduces
the ability to retain water and therefore low cooking characteristics of the
burger.
Color measurement of beef burger
There was a remarkable change in L*-value for all burger samples
after the end of frozen storage (3 months) compared with L* value at zero
time. L*-value for the negative control and NSPI burgers were increased
from 47.4 to 48.6 and 45.08 to 48.47, respectively. L*-value for the SPI,
GLY and NGLY burgers were decreased from 46.97 to 44.96, 46.45 to
43.44 and 46.02 to 43.88 , respectively.
Texture profile analysis (TPA) for burger samples
Nano soy protein isolate and nano glycinin have enhanced the
texture parameters of fresh burger samples and keeping the texture quality
parameters of the frozen burger samples during frozen storage.
Sensory evaluation for beef burger
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SUMMARY
Dina, E. H. Azab (2019), Ph.D., Fac. Agric., Ain Shams Univ.
The results of the sensory evaluation showed significant
differences between the samples of the burger. The samples of the
processed burger using soy protein isolate and nano glycinin recorded
higher scores than the other burger samples and control.
Production of mayonnaise
Microscopic pictures of mayonnaise samples
The large number of the particles surface of nano soy protein
isolate and nano glycinin achieved by the nano processing of soy protein
isolate and glycinin induces a stability effect between oil phase and the
continuous phase of the produced mayonnaise samples.
The results of the production of mayonnaise replaced with 0.5% -
1% - 1.5% of the soybean protein isolate, nano soy protein isolate,
glycinin and nano glycinin as substitution of 50% egg yolk showed a
significant decrease in the sensory acceptance score of the substitution
ratio of 1% and 1.5% compared with commercial mayonnaise and control
(100% egg yolks).
pH- of mayonnaise sample
During the storage period, a slight decrease in pH was observed
with increase in the storage period compared with the control sample.
Commercial mayonnaise had a very low pH compared with the other
samples prepared using soybean proteins.
Color parameters of mayonnaise samples
Color parameters of mayonnaise samples prepared using different
concentrations of soy protein were measured. The L*-values of
mayonnaise supplemented with 0.5 % soy proteins and nano soy proteins
were similar to the L* -values of the commercial control sample and
laboratory control (100% egg yolks) except L*-value of mayonnaise
samples supplemented with 1% and 1.5% soy protein isolate. This
indicates that the increase in the percentage of protein had a negative