ISOLATION AND IDENTIFICATION OF ESCHERICHIA COLI O157:H7 FROM FRESH MILK AND FERMENTED MILK (NONO) IN BENIN CITY, EDO STATE, NIGERIA
Authors: *Igbinosa, E.O, Beshiru, A.
This study was designed to investigate the occurrence of Escherichia coli O157:H7 in fresh and fermented milk (nono) in Benin City, Edo State, Nigeria using standard culture-based and polymerase chain reaction methods. A total of 42 milk samples which comprise of fresh milk (n=18) and fermented milk (n=24) were studied between March and May 2017. The heterotrophic cell count from fresh milk ranged between 4.00×109 and 3.39×1010 cfu/ml while 4.50×109 and 3.65×1010 cfu/ml were observed for the fermented milk. The E. coli O157:H7 cell count from fresh milk ranged from 3.00×104 to 3.12×106 cfu/ml while a range of 1.00×104 to 3.10×106 cfu/ml were observed for the fermented milk. Other E. coli cell count from fresh milk ranged from 1.00×104 to 1.36×106 cfu/ml while a range of 1.00×104 to 1.08×106 cfu/ml were observed for the fermented milk. Faecal coliforms cell counts from fresh milk ranged from 2.00×103 to 6.30×104 cfu/ml while a range of 1.00×103 to 2.76×105 cfu/ml were observed for the fermented milk samples. The population count difference in E. coli O157:H7, other E. coli and faecal coliforms from the fresh and fermented milk samples analysed were statistically significant (p < 0.05). Findings from this study revealed that both the fresh and fermented milk were positive for E. coli O157:H7 as well as other E. coli and faecal coliforms. In addition, the population count from the fresh and fermented milk samples exceeded the permissible limits of European Parliament and of the Council. Therefore, fresh and fermented milk could pose a potential health risk to consumers.
Affiliations: *Applied Microbial Processes & Environmental Health Research Group, Department of Microbiology, Faculty of Life Sciences, University of Benin, PMB 1154, Benin City, Nigeria
Keywords: E. Coli O157:H7, Health Risk, Food Safety, Pathogen, Contamination
Published date: 2018/06/30