Prevalence and biocontrol of shiga toxin-producing Escherichia coli in some beef products

A total of 250 random meat product samples (50 each of minced meat, beef burger, beef sausage, beef kofta and beef luncheon) were collected from different super markets at different localties for detection of Escherichia coli using conventional method and Polymerase chain reaction. Conventional method indicated that E coli could be isolated from of minced meat, beef burger, beef sausage, beef kofta and beef luncheon in a percentage of 46%, 28%, 32% , 36% and 16% respectively. While Polymerase chain reaction detected E coli in of minced meat, beef burger, beef sausage, beef kofta and beef luncheon in a percentage of 38%, 22%, 30%, 32% and 12% respectively. The present study was planned to investigate the presence of Shiga toxin-producing E. coli (STEC) in meat products sample as examined by Vero Cytotoxicity Assay (VCA) and confirmed by Serotyping and Multiplex Polymerase Chain Reaction . The serological identification of shiga-toxin producing E.coli isolated from the examined meat samples were O111, O26, O103 , O119 ,O128 ,O86, O45 ,O146 ,O119 and O121. The second part of this study was planned to explore the effect of Nisin alone or combined with sodium lactate on the growth of E.coli O111:H4. The present results allow to conclude that the best formula to destroy all organisms of E.coli in minced beef is the application of nisin by concentration of 10 ppm and 30 ppm coupled with sodium lactate(0.2) for 24 and 48 hours to obtain a maximum margin of human safety against such serious pathogen.