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العنوان
Studies on vacuum-packed meat products \
المؤلف
El-Khawas,Khaled Mohamed Said .
هيئة الاعداد
باحث / خالد محمد سيد
مشرف / سعد محمود سعد
مشرف / زينب محمود نيازى
مناقش / حسن عبد اللطيف عبد الرحمن
تاريخ النشر
2001.
عدد الصفحات
P202 .;
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
علوم وتكنولوجيا الأغذية
تاريخ الإجازة
1/1/2001
مكان الإجازة
جامعة الزقازيق - كلية الطب البيطرى - قسم الرقابة الصحية على الاغذية
الفهرس
Only 14 pages are availabe for public view

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Abstract

Ninety samples of nine vacuum-packed meat products (ten of each) produced by two factories were
collected from different wholesale retail outlets at Cairo and Giza Govemorates as follows: Factory
I : Frankfurter ”A’’, Salamy ”A”, Beef meat ”Gahez” and Beef meat ”Cooked” and Factory 2:
Frankfurter ”B”, Salamy ”B”, Beef bacon, Rose beef and Luncheon .
Regarding the organoleptic examination all samples of frankfurter




”’A” and ”B”




’ salamy ”A” and ”B” beef meat ”Gahez” and ”Cooked”’




and rose beef were accepted having normal color, odor and texture with mean storage periods of 24,
19, 27, 40, 20, 27 and 20 days. Meanwhile only 90% of luncheon and beef bacon samples were accepted
with mean storage periods of 35 and 36 days.
Mean pH values ± SE of frankfurter ”A” frankfurter ”B” salamy ”A” salamy ”B” beef meat ”Gahez”,
beef meat ”Cooked”, rose beef, luncheon and beef bacon were: 5.66 ± 0.02; 5.58 ± 0.02, 5.68 ± 0.02,
5.8
± 0.04, 5.89 ± 0.03, 5.97 ± 0.07, 5.58 ± 0.02, 5.62 ± 0.03 and 5.71 ± 0.1 1,
respectively.
The mean aerobic plate count (APC) of frankfurter ”A” (1 .2 X 108










± 5.6 X 107










was significantly higher (P < 0.05) than that of frankfurter










”B” (7.6 X I 07 ± 2.5 X I 07 , and for salamy ”A” the mean count was (1.2











X 108 ±2.2 X J 07











was significantly lower (P < 0.05) than that of salamy











”B” (5.3 X I 08 ± 1.1 X 108 . On the other hand the mean APC count of beef meat ”Gahez”, beef
meat ”Cooked’’, rose beef, luncheon and beef












bacon were 4.0 X 107 ± 1.8 X 107












3.3 X 107 ± 1.6 X 107, 1.7 X 108 ± 3.7













X 107, 2.9 X 108 ± 8.6 X 107and 2.5 X 108 ± I. I X 108, respectively.
Similarly the mean psychrotrophic count of frankfurter ”A” (1.8 X
108 ± 7.4 X 107) was significantly lower (P < 0.05) than that of frankfurter ”B” (8.0 X 107 ± 2.2 X
107 , and for salamy ”A” the mean count (2.8 X 108 ± 6.1 X 107) was significantly higher (P < 0.05)
than that of salamy ”B” (6.3 X 108 ± 1.0 X 108 . On the other hand the mean psychrotrophic count
of beef meat ”Gahez”, beef meat ”Cooked”, rose beef, luncheon and beef bacon were 7.5 X 107 ± 3.7 X
107, 5.2 X 107 ±1.8



X 107



3.5 X 108 ± 6.6 X 107



3.4 X 108 ± 7.0 X 107 and 2.5 X 108 ± 9.9 X




107, respectively.
Concerning lactic acid bacteria count the mean of frankfurter ”A” (1.4 X 108 ± 6.9 X 107) was
significantly higher (P < 0.05) than that of frankfurter ”B” (1.1 X 108 ± 3.1 X 107 , and for
salamy ”A” the mean






count (1.3 X 108 ± 2.9 X 107






was significantly lower (P < 0.05) than that






of salamy ”B” (6.6 X 108 ± 1.2 X 108 . On the other hand the mean lactic acid bacteria count of
beef meat ”Gahez”, beef meat ”Cooked”, rose beef,







luncheon and beef bacon were 4.6 X 107 ± 2.0 X 107







3.6 X 107 ±1.9 X








107








2.7 X 108 ± 4.6 X 107, 3.0 X 108 ± 6.4 X 107 and 1.2 X 108 ± 2.5 X 107,








respectively.
Also for anaerobic count the mean of frankfurter ”A” (1.2 X 108 ±
6.1 X 107) was significantly higher (P < 0.05) than that of frankfurter ”B” (6.1 X 107 ± 1.9 X 107
, and for salamy ”A” the mean count (1.2 X 108 ±










2.5 X 107










was significantly lower (P < 0.05) than that of salamy ”B” (3.8











X 108 ± 9.1 X 107 . On the other hand the mean anaerobic count of beef meat ”Gahez”, beef meat
”Cooked”, rose beef, luncheon and beef bacon












were 2.7 X 107 ± 1.4 X 107












3.2 X 107 ±1.7 X 107, 1.3 X 108 ± 1.8 X 107













2.8 X 108 ± 5.0 X 107 and 1.3 X 108 ± 4.3 X 107, respectively.
On the other hand the mean count of B. thermosphacta count for frankfurter ”A” (3.6 X 102 ± 6.7 X
10) was significantly higher (P < 0.05) than that of frankfurter ”B” (2.5 X 102 ± 7 X 10), and for
salamy ”A” the
mean cmmt (3.1 X 102 ± 7 X 10) was significantly higher (P < 0.05) than that of salamy ”B” (2.7 X
102 ± 6.2 X I 0). On the other hand the mean B. thermosphacta count of beef meat ”Gahez”, beef meat
”Cooked”, rose beef, luncheon and beef bacon were 3.7 X 102± 9.2 X 10, 2.9 X 102± 1.9
X 102, 9.0 X 10 ± 1.1 X 10, 4.3 X 102 ± 1.5 X 102 and 7.0 X 102 ± 2.3 X
I 02 , respectively.
There was a good correlation coefficient between aerobic, psychrotrophic, lactic acid bacteria and
anaerobic count. Meanwhile there was no correlation between 13. thermosphacta count and any of the
other bacterial count.
The mean anaerobic sporefonners count of frankfurter ”A”, frankfurter ”B”, salamy ”A”, salamy ”B”,
beef meat ”Gahez”, beef meat ”Cooked’’, rose beef, luncheon and beef bacon were 7.0 X 10 ± 4.7 X I
O, 5.0 X 10 ± 3.4 X l 0, 4.0 X 10 ± 4.0 X 10, 4.0 X 10 ± 4.0 X I O, 1.5 X 10 ±
1.5 X I 0, 2.0 X l 0 ± 2.0 X 10, 2.0 X I 0 ± 2.0 X l 0, I .4 X I 02 ± 7.9 X 10
and 4.0 X IO ± 3. l X 10, respectively.
The study failed to isolate any of the following pathogenic microorganisms; Listeria monocytogenes,
Staphylococcus aureus, Bacillus cereus or any of the Clostridium spp. of public health
significance.
Concerning chemical analysis, the both of TVB-N and TBA remain in the accepted level, while no
correlation was found between their levels and the bacterial count of the samples. On the other
hand all samples contained nitrite levels within the pennissible limit.
Five trials for prolonging of shelf life were adopted on experimentally manufactured frankfurter
samples. franlfurter mixture was divided into 2 parts, the first was stuffed and cooked while
2% sodium lactate was added to the second. Both parts were divided into 3 groups after cooking and
peeling the first was packed directly, the second was dipped into 5o/o sodium sorbate solution and the third was in-pack pasteurized in the second
day of packing
Analysis of variance between the different groups indicated that all treatments significantly
(P<0.5) increased the shelf life (based on bacterial count of 108 cfu/g) of the manufactured
samples than the control one (group 1). For group 1 the shelf life was less than 4 weeks.
Meanwhile, the shelf life reached 5 weeks for each of groups 2, 4 and 5, moreover, pasteurization
(groups 3 and 6) increased the shelf life another week to reach 6 weeks.
The sensory properties still accepted in all groups even in those where the bacterial counts
exceeded 108 cfu/g, the result, which indicate the week correlation between bacterial counts and
organoleptic characters and ensure that the predominant lactic acid bacteria have the lowest effect
on the sensory properties of meat products.
There was a good correlation between different bacterial counts allover the storage period except
for B. thermosphacta count. The result, which indicated that lactic acid bacteria· predominate the
microflora in vacuum-packed meat products.