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Abstract <Part A: QUALITY EVALUATION OF INVESTIGATED SALTED FISH. The present study was performed to monitor the quality of 25 samples of commercially available salted fish (Hydrocynus forskalii). The samples were collected at random from salted fish retail outlets in Assiut governorate. Sensory evaluation revealed that only 3 (12 %) out of the 25 examined samples were unaccepted while the remaining 22 (88%) samples were accepted and graded as good 9 (36%) and medium 13 (52%) qualities. Chemical analysis of the salted fish samples showed that the mean pH values of the skin part of salted fish is 7.04 ± 0.27, while that of muscular part is 6.81 ± 0.35. On the other hand, sodium chloride % in all examined salted fish samples ranged from 10.23 % to 17.55 % with a mean value of 15.03 ± 1.77. Mycological evaluation of salted fish revealed that the levels of mould and yeasts obtained on dicloran rose Bengal chloramphenicol medium at 25°C from skin parts ranged from 40 to 4020 CFUs/g with a mean value of 929.2 CFUs, while from muscular parts they ranged from 0 to 14400 with a mean value of 1079.6 CFUs. However, on 10 % NaCl malt extract agar at 25°C from skin parts ranged from 0 to 1140 with a mean value of 152.08 CFUs, while from muscular parts they ranged from 0 to 282 with a mean value of 77.52 CFUs and on 20 % NaCl malt extract agar at 25°C from skin parts ranged from 0 to 40 with a mean value equals 11.28 CFUs, while from muscular parts they ranged from 0 to 98 with a mean value equals 15.36 CFUs. A total of 30 genera, 75 species and some unidentified species of yeasts, dematiaceous hyphomycetes and sterile mycelia were isolated from all the examined salted fish samples on dicloran rose Bengal chloramphenicol agar (DRBC) (26 genera + 61 species), 10% NaCl malt extract agar (21 genera + 46 species) and 20% NaCl malt extract agar (10 genera + 19 species). The genera were Acremonium, Alternaria, Ascotricha, Aspergillus, Botrytrichum, Byssochlamys, Cladosporium, Cochliobolus, Emericella, Eurotium, Fennellia, Fusarium, Graphium, Neosartorya, Nigrospora, Penicillium, Petromyces, Phoma, Pseudoallescheria, Rhizopus, Scolecobasidium, Scopulariopsis, Setosphaeria, Sporothrix, Stachybotrys, Stemphylium, Syncephalastrum, Trichothecium, Ulocladium and Wallemia. from these genera, 75 species were identified. Aspergillus, Petromyces, Penicillium, yeasts and Cladosporium were the most common fungi recovered on DRBC, whereas they were found in most (10-19 samples of the 25 examined skin and muscular salted fish samples). Aspergillus, Eurotium and Cladosporium were the most common genera recovered on 10% NaCl malt extract agar whereas they were found in most (13-16 samples), while on 20% NaCl malt extract agar, Eurotium, Penicillium, Cladosporium and Aspergillus were isolated in moderate frequency of occurrence of the examined skin and muscular salted fish samples. PART B: QUALITY MONITORING OF EXPERIMENTALLY PREPARED SALTED FISH. |