Microbiological Quality of Raw Cow’s Milk In and Around Bahir Dar City, Ethiopia

Abstract

The study was conducted to investigate microbiological quality of raw cow's milk in and around Bair Dar city. The data were collected through laboratory analysis of raw cow's milk. For this purpose 80 milk samples were collected for platform tests and to analyze the microbiological quality of milk. The laboratory analysis was done in Bahir Dar University school of Food and Biochemical Technology laboratory from December 2017 to January 2018. Based on the result of platform tests on milk quality, out of the total collected and tested milk samples 13.8% were positive with clot on boiling test and 22.5% of samples had positive result with alcohol test which indicates the alcohol test is more sensitive than the clot-on-boiling test. There was a significance difference (p<0.01) in colt on boiling test and (p<0.05) in alcohol test amongst production systems. The highest (0.235±0.008) titratable acidity of raw cow's milk was observed in rural areas. The overall mean coliform count, standard plate count, yeast and mold count and staphylococcus aureus count of raw milk produced in the area were 4.95±0.18 log 10 cfu/ml, 7.11±0.13 log 10 cfu/ml, 4.12±0.14 log 10 cfu/m and 3.36±0.11 log 10 cfu/ml, respectively. The milk samples collected from rural area, cooperatives, unwashed udder, gourd container and unwashed hands revealed poor microbiological quality and are far below milk quality standards. Generally, the raw milk in the area was contaminated with various microorganisms. Therefore, stainless steel milk handling utensils, cooling system, health package and an educational program targeted at behavioral changes on water and milk hygiene are highly warranted.

Hygienic Practices of Vendors and Their Contribution to Coliform, Salmonella, and Shigella Bacteria of Raw Milk at Asella Town, Oromia, Ethiopia

“…After the medium was completely solidified, the surface of the medium was covered with a layer of the diluted sample and then incubated at 37°C for 24 hours. Colonies with characteristics of red-purple, 0.5 mm or greater in diameter, surrounded by a reddish halo were identified for further identification of coliforms [ 26 ]. The red-purple colonies were suspended in nutrient agar for further identification of each coliform based on their biochemical reaction.…”