Only 14 pages are availabe for public view
A total of 120 packages of ground beef (40 each of fresh, frozen and frozen with Soya bean) were purchased from different local retailers in Ismailia province. All the collected samples were examined bacteriologically for detection of Enterobacteriaceae especially Salmonella and E. coli
The obtained results indicated that the incidence of Enterobacteriaceae in the examined ground beef samples was 100%, 75% and 87% in fresh, frozen and frozen with Soya ground beef respectively where their count in the examined ground beef samples ranged from 13x102 to 5x105cfu/g with an average of 6.3x104cfu/g for fresh ground beef, <10 to 4x102cfu/g with an average of 1.4x102cfu/g for frozen ground beef and 2×102 to 7x103 cfu/g with an average of 1.6x103cfu/g for frozen ground beef with Soya bean respectively.
The differences between the Enterobactericae count in the examined fresh ground beef samples and both frozen ground beef samples & frozen ground beef samples with Soya bean were significant while there is a non significant difference between frozen
ground beef samples and frozen ground beef samples with Soya bean (p<0.05).
The Enterobacteriaceae species isolated from the examined ground beef samples were E. coli, Klebsiella oxytoca, Serratia marcescens and Serratia liquefaiens in case of fresh ground beef samples with an incidence of 12%, 50%, 25% and 13% respectively, Proteus vulgaries, E. coli and Enterobacter sakazakii in case of frozen ground beef samples at incidence of 52%, 24% and 24% respectively, while in case of the examined frozen ground beef with Soya bean Klebsiella oxytoca, Proteus vulgaries, Citrobacter freundii, E. coli and Pantoea agglomerans were isolated at incidence of 13%, 50%, 12%, 13% and 12% respectively.
Concerning E. coli the results obtained indicate that its incidence in the examined ground beef samples was 60%, 35%, 48% in fresh, frozen and frozen ground beef with Soya bean respectively. While for Salmonella the obtained results indicate that its incidence in the examined ground beef samples was 0%, 10%, 15% in fresh, frozen and frozen ground beef with Soya bean respectively.
Salmonella serotypes isolated from all the examined ground beef samples were untypeable while the isolated E. coli strains were serologically identified into 20 O-typable strains and 37 O- untypable strains. The 20 O-typable strains were identified as O86, O119 and O158 which defined as EPEC with incidence of 2 (10%) for each, O145 which defined as EHEC with incidence of 4 (20%) and O115 which defined as ETEC with incidence of 10 (50%).
Finally, the significance of isolated bacteria in the examined ground beef samples and its possible sources of contamination as well as some recommendations to improve the quality of these products were discussed.