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Abstract Two hundred samples (50 each) of raw milk, ice cream, Domiati cheese and cooking butter were collected from different localities in Gharbia Governorates and examined bacteriologycally and mycologically for detection, count, isolation and identification of Enterobacteriaceae and fungal contamination. Total Enterobacteriaceae count: The mean count of Enterobacteriaceae in one ml of raw milk, ice cream, Domiati cheese and cooking butter were 1.13x108 + 0.39x108، 1.52x104 + 0.34x104 ، 7.42x104 + 2.34x104 and 1.78x104 + 0.31x104, with incidence in percentage of 92 , 62 , 64 and 98%, respectively. Coliform count (MPN/100 ml or g.): The mean count value of coliform /ml for raw milk, Ice cream, Domiati cheese and cooking butter were 3.88x106 + 2.91x106, 1.98x103 + 0.49x103, 8.89x103 + 4.09x103 and 2.37x103 + 0.57x103, with percentage of 88, 54, 46, and 84% respectively. Enterobacteriaceae isolates: E. coli, Klebsiella pneumoniae, K. ozaenae, Enterobacter cloacae, E. aerogenes, E. hafniae, E. agglomerans, Citrobacter freundii, Cit. diversus, Proteus vulgaris, P. mirabilis, P. rettgeri, Serratia marcescens, ( Summary S. liquefaciens were isolated from milk in percentage of 14, 28, 18, 22,42, 8, ــ , 54 , 24 , 38 , 16 and 14% respectively. The same isolates from ice cream were in percentage of 4, 6, 14, ــ , 16 , ــ , 4 , 18 , ــ , 14 and 22% and those from Domiati cheese were in percentage of 10, 40, 24, 28, 18, ــ , ــ , 36 , 16 , 58 , 14 , 22 , 12 and 20%, while the isolates from cooking butter were in percentage of 6, 22, 8, 40, ـــ , 12 , ـــ , 16 , 22 , 14 , 12 and 4% respectively. Salmonella typhimurium could be isolated from one sample (2%) of both examined milk and ice cream samples and two samples (4%) of Domiati cheese. Serological typing proved that the isolated strains have the antigenic structure of O: 1, 4, (5), 12, H : I 1,2 and belonged to group (B). Salmonella entritidis could be isolated from 3 samples of raw milk (6%) and sample of Domiati cheese (2%). Serological typing proved that the isolated strain have the antigenic structure of O: 1, 9, 12 and belonged to group (D). - Salmouella failed to be detected in all examinead cooking butter samples. - Serological typing of E. coli strains of which isolated from raw milk, ice cream, Domiati cheese and cooking butter samples were belonged ( Summary to four serovars O55: K59 (B5) , O119: K69 (B19) , O124: K72 (B17) and O127: K63 (B8). Total yeast count: Yeast could be detected in 70, 64, 66 and 88% of examined samples of raw milk, ice cream, Domiati cheese and cooking butter, respectively. The mean total yeast count values were 9.40x105+4.17x105, 7.16x104 + 2.67x104 , 1.21x104 + 4.55x104 and 7.53x105+3.29x105 respectively. Total mould count: Mould could be detected in 68, 52, 58 and 84% of examined samples of raw milk, ice cream, Domiati cheese and cooking butter respectively. The mean total moulds count were 1.35 x 105 + 0.52 x 105, 2.45 x 103 + 0.82 x 103, 1.99 x 104 + 0.80 x 104 and 9.22 x 104 respectively. Yeast isolates: Condida albicans, C. Krusei, C. tropicalis, Rhodotorula minuta, R. rubra. Soccharomyces cervisiae, S. dairvensis, Torulopsis candida, T. famata, T. halmii could be isolated from raw milk, ice cream, Domiati cheese and cooking butter samples at various percentage. Mold isolates: ( Summary Alternaria alternate, Aspergillus flavus, A. fumigatus A. nidulans, A. niger, A. ochraceus, A. terreus, A. versicolor, Cladosporium resinae, C. herbarum, Fusarium nivale, F.tricinctum, F. Oxysporum, Mucor mucedo, M. racemosus, Penicillium brevicompactum, P. citrinum, P. expansum, P. requeforti, P. verrucosum, Rhizopus stolonifer and Thamindium elegans could be isolated from raw milk, ice cream, Domiati and cooking butter samples at different percentage. Screening of Aspergillus flavus for aflatoxin production 18 out of 31 strains of Aspergillus flavus isolated from the examined milk and its products samples proved to have the ability for aflatoxin production. The quantities of AFB1 produced by aflatoxigenic of A. flavus strains isolated from raw milk (5/55%), ice cream (3/60%), Domiati cheese (3/50%) and cooking butter (7/63.6%) were 30.54+4.01, 13.99 + 1.78, 10.13 + 1.24 and 34.86 + 3.59 (Mg/ L. media) respectively. On the other side the quantities of AFB2 produced by A. flavus strains isolated from raw milk, ice cream, Domiati cheese and cooking butter samples were 3.69+0.70, 2.43+0.51, 1.92+0.27 and 4.13+0.82 (Mg/ L. media) respectively . The public health importance and hygienic significance of isolates as well as the suggested measures for improving the quality of raw milk, ice cream Domiati cheese and cooking butter have been discussed. |