Assessment of Microbial Contaminants (enterobacteria) in Street Vended Cow’s Raw Milk in Dodoma City, Tanzania

Carolyne Charles Ruhembe
St. John’s University of Tanzania
Email: cruhembe@sjut.ac.tz

Abstract: This study was conducted on street vended raw milk to determine their microbial contamination in four selected wards of Dodoma urban district, Tanzania. A cross-sectional study was conducted on a statistically convenient sample size (N=60) of raw milk collected from street vendors in four selected wards of Dodoma city centre. Laboratory analysis was conducted in the biology laboratory, Department of Biology of St John’s University of Tanzania. Mac Conkey, EC broth, Eosin Methylene Blue Agar (EMB AGAR) were used for culturing microorganisms. Biochemical tests were performed to confirm the presence of coliforms by using sugar fermentation, as well as the use of nutrient agar in culturing microorganisms for MPN [Most Probable Number], following the serial dilutions method. E. coli, Salmonella spp. and Krebsiella spp. were detected in 20/60 (31.33%), 6/60 (10%) and 5/60 (8.33%) of raw milk samples. Plastic containers were commonly used for storage and transportation of milk. The present study showed that the quality of milk in the study areas were poor. High MPN were over and above the recommended East Africa Community standards. The contamination was due to poor hygienic practices during milking, inappropriate transportation and storage facilities, for example packaging materials, lack of cooling systems and use of unsafe water. There is therefore the need to plan and offer simple and practical training courses on hygienic handling of milk for milk handlers in order to ensure safety of raw milk.