الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 153 |  |  |
| | | from | 153 | | |
Abstract
The present investigation was designed to study the quality of 125 samples of seafish products consisted of 25 each of smoked fish fillets glass jared, packaged and unpackaged smoked fish, smoked roe glass jared, roe of packaged and unpackaged smoked fish and salted sardine fillets glass jared which were collected from different supermarkets and fish sale retail outlets in Assiut, Cairo and Alexandria cities.
Sensory assessment as a mean of determining quality showed that 124 out of 125 examined fish product samples (99.2%) were accepted and graded into class good 36 (28.8%) and class medium 88 (70.4%). Only one sample (0.8%) was considered unaccepted.
Chemical analysis of the examined fish product samples revealed that neither nitrate nor nitrite could be detected. The mean pH values of the examined smoked fish fillets glass jared, packaged and unpackaged smoked fish, smoked roe glass jared, roe of packaged and unpackaged smoked fish and salted sardine fillets glass jared were 6.37 ± 0.015,6.38 ± 0.019,6.16 ± 0.04,6.24 ± 0.016 and 6.34 ± 0.013, respectively whereas the mean sodium chloride contents were 9.09 ± 0.44, 10.93 ± 0.44, 10.16 ± 0.35, 10.12 ± 0.39 and 13.98 ± 0.36% in the examined samples respectively. As fore total volatile base nitrogen (TVBN) of the aforesaid fish products, their mean values were 82.77 ± 8.89, 74.92 ± 5.55, 60.87 ± 3.93, 72.06 ± 5.40 and 53.87 ± 6.48 mg N / 100 g muscle.
A significant difference in the pH values, sodium chloride and total volatile base nitrogen contents was observed between some of the examined fish product samples.
Regarding the microbiological status of the examined fish product samples, the mean aerobic plate count (APC) values of the examined smoked fish fillets glass jared, packaged and unpackaged smoked fish, smoked roe glass jared, roe of packaged and unpackaged smoked fish and salted sardine fillets glass jared were 3 x 105 ± 1.1 x 105, 1.36 x106 ± 5.4x 105, 1.6 x 105 ± 6.4 x 104, 1.36 X 106 ± 5.8 x 105 and 2.77 x 104 ± 1.45 x 104 cfu / g, respectively. Most of the examined samples (31.2%) had APC within the range 104 - < 105 / g. A significant difference in the mean value of APC was noticed between some of the examined fish product samples.
As for halophiles, the mean counts of the above mentioned fish products were 1.18 x 106 * 5.6 X 105, 3.5 X 106 ± 1.91 x 106, 1.23 X 106 ± 6.9 x 105, 3.8 X 106 ± 2.6 x 106 and 3.5 x 105 ± 3.3 x 105 cfu / g, respectively. Most of the examined samples (24%) had halophilic count within the range 105 - 106 / g. Variations in the mean value of halophilic bacterial count between the different examined fish products were non significant.
Concerning Staph aureus count, the mean values of the tested fish product samples were 1.95 x 104 ± 6.9 x 103,4.6 X 103 ± 2.23 x 103, 5.2 X 104 ± 3.3 x 104 , 3 X 104 ± 2.99 x 104 and 5.3 x 102 ± 2.3 x 102 cfu / g, respectively. Most of the examined samples (57.6%) had <10 Staph. aureus / g while 4 samples (3.2%) had a count over 105 / g. However, out of 125 fish product samples examined 78 samples contained Staph aureus (62.4%) where 20 strains (25.6%) proved to be coagulase-positive and 58 strains (74.4%) were coagulase-negative Staph
aureus.
Enterobacteriaceae were existed in low numbers in the examined smoked
fish fillets glass jared, smoked roe glass jared and roe of packaged and unpackaged smoked fish. Detectable counts could be observed in 9 out of the 125 examined fish product samples (7.2%) from which 4 samples had a count greater than 104 / g.
The present investigation was designed to study the quality of 125 samples of seafish products consisted of 25 each of smoked fish fillets glass jared, packaged and unpackaged smoked fish, smoked roe glass jared, roe of packaged and unpackaged smoked fish and salted sardine fillets glass jared which were collected from different supermarkets and fish sale retail outlets in Assiut, Cairo and Alexandria cities.
Sensory assessment as a mean of determining quality showed that 124 out of 125 examined fish product samples (99.2%) were accepted and graded into class good 36 (28.8%) and class medium 88 (70.4%). Only one sample (0.8%) was considered unaccepted.
Chemical analysis of the examined fish product samples revealed that neither nitrate nor nitrite could be detected. The mean pH values of the examined smoked fish fillets glass jared, packaged and unpackaged smoked fish, smoked roe glass jared, roe of packaged and unpackaged smoked fish and salted sardine fillets glass jared were 6.37 ± 0.015,6.38 ± 0.019,6.16 ± 0.04,6.24 ± 0.016 and 6.34 ± 0.013, respectively whereas the mean sodium chloride contents were 9.09 ± 0.44, 10.93 ± 0.44, 10.16 ± 0.35, 10.12 ± 0.39 and 13.98 ± 0.36% in the examined samples respectively. As fore total volatile base nitrogen (TVBN) of the aforesaid fish products, their mean values were 82.77 ± 8.89, 74.92 ± 5.55, 60.87 ± 3.93, 72.06 ± 5.40 and 53.87 ± 6.48 mg N / 100 g muscle.
A significant difference in the pH values, sodium chloride and total volatile base nitrogen contents was observed between some of the examined fish product samples.
Regarding the microbiological status of the examined fish product samples, the mean aerobic plate count (APC) values of the examined smoked fish fillets
glass jared, packaged and unpackaged smoked fish, smoked roe glass jared, roe of packaged and unpackaged smoked fish and salted sardine fillets glass jared were 3 x 105 ± 1.1 x 105, 1.36 x106 ± 5.4x 105, 1.6 x 105 ± 6.4 x 104, 1.36 X 106 ± 5.8 x 105 and 2.77 x 104 ± 1.45 x 104 cfu / g, respectively. Most of the examined samples (31.2%) had APC within the range 104 - < 105/ g. A significant difference in the mean value of APC was noticed between some of the examined fish product samples.
As for halophiles, the mean counts of the above mentioned fish products were 1.18 x 106 * 5.6 X 105, 3.5 X 106 ± 1.91 x 106, 1.23 X 106 ± 6.9 x 105, 3.8 X 106 ± 2.6 x 106 and 3.5 x 105 ± 3.3 x 105 cfu / g, respectively. Most of the examined samples (24%) had halophilic count within the range 105 - 106 / g. Variations in the mean value of halophilic bacterial count between the different examined fish products were non significant.
Concerning Staph aureus count, the mean values of the tested fish product
. samples were 1.95 x 104 ± 6.9 x 103,4.6 X 103 ± 2.23 x 103, 5.2 X 104 ± 3.3 x 104 , 3 X 104 ± 2.99 x 104 and 5.3 x 102 ± 2.3 x 102 cfu / g, respectively. Most of the examined samples (57.6%) had <10 Staph. aureus / g while 4 samples (3.2%) had a count over 105 / g. However, out of 125 fish product samples examined 78 samples contained Staph aureus (62.4%) where 20 strains (25.6%) proved to be coagulase-positive and 58 strains (74.4%) were coagulase-negative Staph
aureus.
Enterobacteriaceae were existed in low numbers in the examined smoked
fish fillets glass jared, smoked roe glass jared and roe of packaged and unpackaged smoked fish. Detectable counts could be observed in 9 out of the 125 examined fish product samples (7.2%) from which 4 samples had a count greater than 104 / g.
As for coliforms, 115 out of the 125 examined fish product samples (92%) had non detectable levels «3/ g) wheras 10 samples (8%) were contaminated with such organisms in levels varied from 3 to 1.1 x 103 MPN / g. whereas, 15 samples only (12%) showed countable levels of Cl. perfringens.
The identified Aeromonas spp. which were recovered from the examined fish product samples were A. hyDROPhila, A. caviae and A. sobria which constituted 19.2, 11.2 and 5.6 % of the 125 examined samples.
Members of Enterobacteriaceae recovered from the examined fish product samples were Citrobacter diversus (10.26%), -Edwardsiella ictaluri (2.56%), Entetobacter aerogenes (2.56%), Enterobacter agglomerans (12.82%), Erwinia herbicola (7.69%), E. coli (2.56%), Klebsiella atlantae (2.56%) Klebsiella edwardsii (5.13%), Klebsiella oxytoca (2.56%), Klebsiella ozaenae (2.56%), Klebsiella pneumoniae (7.69%), Klebsiella unnamed (2.56%), Morganella m organ ii (7.69%), Salmonella spp. (5.13%), Serratia marcescens (2.56%), Serratia odorifera (2.56%), Serratia rubidaea (2.56%), Shigella boydii (2.56%), Shigella dysenteriae (5.13%) and Shigella sonnei (10.26%).
Yersinia enterocolitica. Y: frederiksenii, Y: intermedia and Y: Kristensenii were existed in 6.4,4,3.2 and 2.4% of the 125 examined fish product samples, but Lisferia monocytogenes failed to be recovered from any sample.
The public health significance of the isolated microorganisms from the examined fish product samples was discussed and suggestive measures to protect the consumer and produce high quality fish products were outlined.