Physicochemical Properties and Microbial Quality of Raw Cow Milk Produced by Smallholders in Bench Maji-Zone, Southwestern Ethiopia

Abstract

The study was conducted in Bench Maji-Zone, Southwestern Ethiopia, aimed to assess physicochemical properties and microbial quality of raw cow’s milk produced by smallholders in the areas. A total of Forty five samples of raw cow’s milk were collected from Mizan Aman, Debub and Shei Bench Woredas. All of the samples were collected using proportional random sampling method. The mean values for pH, specific gravity, titratable acidity, fat, protein and ash contents of milk samples collected from Mizan Aman were 6.153±0.114, 1.022±0.016, 0.215±0.010, 5.867±0.586, 3.844±0.475 and 0.780±0.050, respectively. The mean values for pH, specific gravity, titratable acidity, fat, protein and ash contents of milk samples collected from Debub Bench Woreda were 6.647±0.200, 1.031±0.002, 0.174±0.018, 5.973±0.730, 3.954±0.402 and 0.815±0.047, respectively. Whereas, milk samples obtained from Shei Bench Woreda had 6.627±0.128, 1.031±0.001, 0.177±0.013, 6.233±0.940, 4.140±0.320 and 0.791±0.066 for pH, specific gravity, titratable acidity, fat, protein and ash contents, respectively. Significant differences (P<0.05) were found for the values pH, specific gravity, titratable acidity, fat, protein and ash contents between the sources of milk samples. The average (±SD) total bacterial count, coliform count, spore-forming bacterial count and yeast and mould count of milk samples obtained from Mizan Aman were 7.235±0.277log₁₀ cfu/ml, 5.203±0.230log₁₀ cfu/ml, 6.489±0.258log₁₀ cfu/ml and 4.001±0.588log₁₀ cfu/ml, respectively. Whereas, milk samples obtained from Debub Bench Woreda had 7.222±0.156log₁₀ cfu/ml, 5.187±0.211log₁₀ cfu/ml, 6.307±0.195log₁₀ cfu/ml and 3.944±0.346log₁₀ cfu/ml for total bacterial count, coliform count, spore-forming bacterial count and yeast and mould count, respectively. On the other hand, the corresponding values for Shei Bench Woreda samples were 6.817±0.381log₁₀ cfu/ml, 4.911±0.324log₁₀ cfu/ml, 6.221±0.542log₁₀ cfu/ml and 3.762±0.468log₁₀ cfu/ml, respectively. Total bacterial  count, coliform count, spore-forming bacterial count and yeast and mould count of milk samples obtained from Mizan Aman were significantly higher (P<0.05) than milk samples obtained from Debub and Shei Bench Woredas. Therefore, it was concluded that the physicochemical properties was adequate as compared to the standard level whereas, the microbial quality of raw cow’s milk produced by smallholders in the areas was poor and this suggests the need for enriched hygienic practices and educating the public on safety issues and personal hygiene in milk handling.

Keywords: Bench Maji, Microbial quality, physicochemical properties, Raw cow milk.