الفهرس 
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Abstract
This study was conducted to determine the chemical composition of grape (seeds and peels). Determination of some active compounds
using High Performance Liquid chromatography (HPLC). Applying of
different concentrations of this powder in some meat products such as
sausage and compared with synthetic antioxidants (BHT). Sensory
evaluation of these products will do to select the best accepted
concentration without effect of sensory evaluations. Determination the
stability of these antioxidants (natural and synthetic) during frozen
storage at -18 °C for 6 months by determined the fat rancidity as
indicator of efficiency of these antioxidants to reduce fat analysis and
rancidity. Microbiological quality of sausages during frozen storage
will also determine.
The obtained results could be summarized in the following:
5.1. Active compounds of grape seeds and peels:
5.1.1 Total phenolic content and yield of grape seeds:
5.1.1.1. The yield of grape seeds samples was 9.84±0.359 %, while
the samples total phenolic content of grape seeds was reached
526.55±9.97 mg/ g-1 extract.
5.1.2. Phenolic compounds of grape seeds:
1. The grape seeds extract contains different amounts of Gallic
acid, t-Coutaric acid, e Caffeic acid, e p-Coumaric acid, (+)-
catechin, (-)-epicatechin gallate, (-)-epicatechin and procyanidin
B2. The values were 0.850 ± 0.012, 0.006 ± 0.001, 0.004 ±
0.001, 0.011 ± 0.005, 1.130 ± 0.14, 0.013 ± 0.002, 7.450 ± 0.32
and 2.330 ± 0.17 mg/g DM, respectively.
2. d-Quercetin-glucoside, Rutin, Luteolin-glucoside , Myricetinglucoside,
Kaempferol-glucoside, Quercetin, Delphinidin-3-
glucosidea,Cyanidin- 3- glucoside, Petunidin- 3-glucosideb,
Peonidin-3-glucosideb , Malvidin-3-glucoside, Sum of glucoside
derivativesc not detected.
5.1.3. Total phenolic content and yield of grape
peels:
1. The yield of grape peels samples was 3.69±0.226 %, while the
total phenolic content of grape seeds reached 254.52±8.86 mg g-
1 extract.
5.1.4. Phenolic compounds of grape peels:
1. The grape peels extract contains different amounts of phenolic
compounds such as Gallic acid, t-Coutaric acid, e Caffeic acid, e
p-Coumaric acid, (+)-catechin, (-)-epicatechin gallate, (-)-
epicatechin and procyanidin B2. The values were 0.380c ± 0.015,
0.002d ± 0.001, 0.001d ± 0.001, 0.003d ± 0.005, 0.283b ± 0.14,
0.003d ± 0.002, 1.862a ± 0.32 and 0.582b ± 0.17 mg/g DM,
respectively.
2. d- Quercetin-glucoside, Rutin, Luteolin-glucoside, Myricetinglucoside,
Kaempferol-glucoside, Quercetin, Delphinidin-3-
glucosidea,Cyanidin-3-glucoside,Petunidin-3-glucosideb,peonidi
Peonidin- 3-glucosideb , Malvidin-3-glucoside, Sum of glucoside
derivativesc not detected.
Sausage quality:
5.2. Chemical composition of fresh sausages with
different levels of grape seeds:
1. Control sausage (without grape seeds) recorded the highest
moisture, protein and fiber content (%), the values were 61.66%,
14.78% and 0.25%, respectively.
2. Sausage with BHT recorded the highest ash content and lowest
carbohydrates contents. The values were 2.04% and 2.60%,
respectively.
3. Increasing grape seeds levels to the sausages showing the highest
moisture, ash and fiber contents. The values were 61.49% and
1.81% and 0.05%, respectively.
5.2.1. Chemical composition of sausages as
influenced by addition of different levels of
grape seeds during frozen storage at -18 °C for 6
months:
1. The highest protein and fiber content, and lowest energy value
were recorded in control sausages after 3 months of storage
period. The values were 14.66%, 0.27% and 251.96 kcal/100g,
respectively.
2. Increasing grape seeds levels (600mg/kg) in sausages, the fat,
ash, fiber, carbohydrates and energy value contents increasing.
The highest values recorded in sausage with 600 mg/kg grape
seeds after 3 months of storage period. The values were 21.87,
1.78, 0.15, 3.53%, and 267.31 kcal/100g, respectively.
3. The highest moisture and protein contents and lowest energy
value were recorded in control sausages after 6 months of
storage period. The values were 58.31%, 13.85% and 256.40
kcal/100g, respectively.
4. Increasing grape seeds levels up to 600 mg/kg in sausages after 6
months of storage period recorded the highest fat, ash, fiber and
carbohydrates content. The values were 23.64, 2.05, 0.19, and
4.76%.
5. With progress of storage period, the moisture and protein content
decreased, while fat, ash, fiber, carbohydrates and energy value,
increased.
5.2.2. Chemical composition of fresh sausages
with different levels of grape peels:
1. Control sausage (without grape peels) recorded the highest
moisture, protein and fiber content (%), the values were 61.66%,
14.78% and 0.25%, respectively.
2. Increasing grape peels levels (600 mg/kg) to the sausages
showing the highest fat, ash and fiber contents. The values were
19.43% and 1.81% and 0.04%, respectively.
5.2.3. Chemical composition of sausages as
Influenced by addition of different levels of
grape peels during frozen storage at -18 °C for 6
months:
1. The highest protein and fiber contents and lowest energy value
were recorded in control sausages and sausage with 100 mg/kg
BHT, respectively during frozen storage at -18 °C for 3 months.
The values were 14.66%, 0.27% and 250.83 kcal/100g,
respectively.
2. Increasing grape peels levels in sausages, the fat, ash, fiber,
carbohydrates and energy value contents increasing.
3. The highest values recorded in sausage with 600 mg/kg grape
peels during frozen storage at -18 °C for 3 months. The values
were 20.47, 2.37, 0.06, 3.25%, and 253.78 kcal/100g,
respectively.
4. The highest moisture and protein contents were recorded in
control sausages during frozen storage at -18 °C for 3 months.
The values were 59.23%, and 14.01%, respectively.
5. Increasing grape peels levels up to 600 mg/kg in sausages during
frozen storage at -18 °C for 3 months recorded the highest fat,
ash, carbohydrates and energy value contents. The values were
22.29, 2.60, 3.35% and 266.41kcal/100g, respectively.
6. With progress of storage period, the moisture and protein content
decreased, while fat, ash, fiber, carbohydrates and energy value,
increased.
5.4. Thiobarbituric acid value (TBA):
5.4.1. Thiobarbituric acid value of sausages as
influenced by addition of different levels of
grape seeds during storage period at – 18 °C for
6 months:
1. At zero time of storage period at -18 °C the values of TBA were
0.32mg / kg for control sausage.
2. With progress of storage period (3 months) the values of all
tested sausages increased. The values were 0.85, 1.05, 0.5, 0.52
and 0.47 mg / kg, for control sausage, sausage with BHT,
sausage with 100, 300 and 600 mg/kg grape seeds, respectively.
3. At the end of frozen storage (6 months) at– 18 °C the TBA
recorded the highest values with all tested sausage samples by
different rates. The values were 1.54, 1.30 and 1.35, 1.26 and
0.86 mg / kg for the same mentioned tested sausage respectively.
4. The sausage with 600 mg/kg grape seeds recorded the lowest
T.B.A. value due to higher antioxidation activity of grape seeds
during frozen storage period.
5.4.2. Thiobarbituric acid value of sausages as
influenced by addition of different levels of
grape peels during storage period at – 18 °C for
6 months:
1. At zero time of storage period at -18 °C the values of TBA were
0.32mg / kg for control sausage.
2. With progress of storage period (3 months) the values of all
tested sausages increased. The values were 0.85, 1.05, 0.55, 0.56
and 0.50 mg/ kg, for control sausage, sausage with BHT, sausage
with 100, 300 and 600 mg/kg grape peels, respectively.
3. At the end of frozen storage period (6 months) at– 18 °C the
TBA recorded the highest values with all tested sausage samples
by different rates. The values were 1.54, 1.29 and 1.41, 1.31 and
0.95 mg / kg for the same mentioned tested sausage respectively.
4. The sausage with 600 mg/kg grape peels recorded the lowest
T.B.A value.
5.5. Physical properties of sausages:
5.5.1. Physical properties of sausages as influenced
by addition of different levels of grape seeds
during frozen storage at -18 °C for 6 months:
1. The value of water holding capacity (WHC) of sausages at zero
time of storage period was 3.2 cm2.
2. With advancement of storage period for 3 months, the values of
WHC decreased by different rates. The values were 2.75, 2.74,
2.76, 2.77 and 2.79 cm2, respectively for control sausage,
sausage with BHT, sausage with 100, 300 and 600 mg/kg grape
seeds after 3 months of frozen storage.
3. The lowest W. H.C. values recorded at the end of storage period.
The values were 1.50, 1.50, 1.52, 1.54 and 1.56 cm2, respectively
for the same mentioned tested sausages.
4. A markedly decrease of plasticity was observed during storage
of sausages with grape seeds, and it recorded the maximum
decrease at the end of storage period The plasticity decreased
from 4.24 to 2.5, 4.24 to 2.49, 4.24 to 2.52, 4.24 to 2.54 and 4.24
to 2.56cm2, respectively for control sausage, sausage with BHT,
sausage with 100, 300 and 600 mg/kg grape seeds after 6 months
of frozen storage period.
5. The values of cooking loss and yield were 25.40 % and 74.60 %,
respectively for control sausage.
6. With progress of storage period for 3 months a marked increase
in cooking loss and decrease in yield was observed. The values
were 33.75 & 66.25 %, and 33.70 & 66.30, 33.30 & 66.70, 33.00
& 67.00 and 32.86 & 67.14, respectively for control sausage,
sausage with BHT, sausage with 100, 300 and 600 mg/kg grape
seeds.
7. The highest increase in cooking loss and decrease in yield was
recorded at the end of storage period (6 months). The values
were 39.80 % & 60.20 %, 39.72 % & 60.28, 39.50 & 60.50,
39.22 & 60.78 and 38.90 & 61.10, respectively for control
sausage, sausage with BHT, sausage with 100, 300 and 600
mg/kg grape seeds.
5.5.2. Physical properties of sausages as influenced
by addition of different levels of grape peels
during frozen storage at -18 °C for 6 months:
1. The value of water holding capacity (WHC) at zero time of
storage period was 3.2 cm2.
2. With progress of storage period for 3 months, the values of
WHC decreased by different rates. The values were 2.75, 2.74,
2.75, 2.76 and 2.77 cm2, respectively for control sausage,
sausage with BHT, sausage with 100, 300 and 600 mg/kg grape
peels after 3 months of frozen storage.
3. The lowest W. H.C. values recorded at the end of storage period
(6 months). The values were 1.50, 1.50, 1.51, 1.53 and 1.54 cm2,
respectively for the same mentioned tested sausages.
4. A markedly decrease during storage of sausages with grape
peels, and it recorded the maximum decrease at the end of
storage period. The plasticity decreased from 4.24 to 2.5, 4.24 to
2.49, 4.24 to 2.51, 4.24 to 2.53 and 4.24 to 2.54cm2, respectively
for control sausage, sausage with BHT, sausage with 100, 300
and 600 mg/kg grape peels after 6 months of frozen storage
period.
5. The values of cooking loss and yield for control sausage with
during frozen storage at -18 °C. The values were 25.24 % and
74.76 %, respectively.
6. With advancement of storage period for 3 months a marked
increase in cooking loss and decrease in yield was observed. The
values were 33.75 and 66.25 %, and 33.73 & 66.27, 33.36 &
66.64, 33.10 & 66.90 and 32.93 & 67.07, respectively for control
sausage, sausage with BHT, sausage with 100, 300 and 600
mg/kg grape peels.
7. At the end of storage period (6 months) the highest increase in
cooking loss and decrease in yield were observed. The values
were 39.80 % & 60.20 %, 39.78 % 60.22, 39.66 & 60.34, 39.35
& 60.65 and 38.96 & 61.04, respectively for the same mentioned
tested sausages.
5.6. Microbiological aspects
5.6.1. Microbiological aspects of fresh sausages as
influenced by addition of grape seeds
during storage at -18 °C for 6 months.
1. At zero time of frozen storage the counts of all tested
microorganisms (E. coli, Salmonella sp., Bacillus cereus,
Staphylococcus aureus, Aspergillus niger and Candida albicans)
were 1.0 x 106 cfu / g.
1. With advancement of storage period (3 months) at – 18 °C of
sausage with different levels of grape seeds the counts of all
tested microorganisms in sausage samples greatly decreased. The
counts were 8.3 x 104, 1.2 x 105, 8.4 x 103, 7.5 x 104, 5.3 x 104
and 7.0 x 104 cfu / g for E. coli, Salmonella sp., Bacillus cereus,
Staphylococcus aureus, Aspergillus niger and Candida albicans,
respectively.
2. At the end of storage period for 6 months at – 18 °C the counts
of all tested microorganisms in sausage samples recorded the
highest inhibition by more different rates (percent decrease
ranged (99.0 – 99.16 %). The counts were 3.0 x 103, 1.0 x 104,
1.5 x 103, 1.2 x 103, 3.1 x 103 and 2.0 x 103 cfu / g for E. coli,
Salmonella sp., Bacillus cereus, Staphylococcus aureus,
Aspergillus niger and Candida albicans, respectively.
5.6.2. Microbiological aspects of fresh sausages as
influenced by addition of grape peels
during storage at -18 °C for 6 months.
1. At zero time of frozen storage the counts of all tested
microorganisms (E. coli, Salmonella sp., Bacillus cereus,
Staphylococcus aureus, Aspergillus niger and Candida albicans)
were 1.0 x 106 cfu / g in sausage samples with grape peels.
2. With advancement of storage period up to 3 months at– 18 °C
the counts of all tested microorganisms in sausage samples with
grape peels slightly decreased. The counts were 4.2 x 104, 5.1 x
104, 4.0 x 103, 8.5 x 104, 7.2 x 104 and 7.8 x 104 cfu / g for E.
coli, Salmonella sp., Bacillus cereus, Staphylococcus aureus,
Aspergillus niger and Candida albicans, respectively.
3. At the end of storage period for 6 months at – 18 °C the counts
of all tested microorganisms in sausage samples recorded the
highest decrease by different rates. The counts were 5.0 x 103,
2.0 x 103, 1.5 x 102, 0.4 x 103, 1.5 x 102 and 2.1 x 102 cfu / g for
E. coli, Salmonella sp., Bacillus cereus, Staphylococcus aureus,
Aspergillus niger and Candida albicans, respectively.
4. The sausage with grape seeds had higher inhibitory effect for all
tested microorganisms than that of sausage with grape peels
during storage period for 6 months at -18 °C, showing percent
decrease of (91.5 – 99.60 % )for grape seeds and (88.0 -
99.16%) for grape peels, respectively.
5.7. Organoleptic properties:
5.7.1. Organoleptic properties of sausages as
influenced by addition of different levels of
grape seeds during frozen storage at -18 °C for
6 months:
1. At zero time of frozen storage at -18 °C all organoleptic
properties (color, flavor, taste, texture and overall acceptability)
of sausage with grape seeds recorded the highest organoleptic
score (9) of the judging scale.
2. With progress of storage period for 3 months all tested
organoleptic properties of all investigated sausages somewhat
decreased. The scores ranged from (8.1 to 8.3) for color, (8.0 to
8.2) for flavor, (8.2 to 8.4) for taste, (8.0 to 8.1) for texture and
(8.0 to 8.2) for overall acceptability.
3. While at the end of storage period (6 months) a markedly
reduction in all organoleptic properties was observed. The scores
ranged from (7.1 to 7.4) for color, (7.3 to 7.5) for flavor, (7.2 to
7.4) for taste, (7.0 to 7.2) for texture and (7.1 to 7.4) for overall
acceptability, respectively.
4. The sausages with grape seeds were somewhat of better quality
than that prepared with control sausage considering the
organoleptic properties.
5.7.2. Organoleptic properties of sausages as
influenced by addition of different levels of
grape peels during frozen storage at -18 °C for 6
months:
1. At zero time of frozen storage at -18 °C all organoleptic
properties (color, flavor, taste, texture and overall acceptability)
of sausage with grape peels recorded the highest organoleptic
score (9) of the judging scale.
2. With advancement of storage period for 3 months all tested
organoleptic properties of all investigated sausages somewhat
decreased. The scores ranged from (8.1 to 8.3) for color, (8.0 to
8.2) for flavor, (8.2 to 8.4) for taste, (8.0 to 8.1) for texture and
(8.0 to 8.2) for overall acceptability, respectively.
3. At the end of storage period (6 months) a markedly reduction in
all organoleptic properties was observed. The scores ranged from
(7.1 to 7.4) for color, (7.3 to 7.5) for flavor, (7.2 to 7.4) for taste,
(7.0 to 7.2) for texture and (7.0 to 7.3) for overall acceptability,
respectively.
4. Finally, the sausages with grape seeds were somewhat of better
quality than that prepared with control or peels sausages
considering the organoleptic properties.