Physical Properties and Chemical Compositions of Raw Cow Milk in Milk Shades Around Addis Ababa, Ethiopia

摘要

Milk has an important diet for humans and animals. The aim of this study was to evaluate the physical property and chemical composition of raw cow’s milk in central highlands of Ethiopia. Raw milk samples of 240 were collected from four sites of Wolmera, Selale, Sebeta, and Debrezeit for physical and chemical composition analysis. Physical parameters of pH, titratable acidity, specific gravity, freezing point and chemical composition of total solids, protein, fat, ash and lactose were tested in this study. The result showed that there is no significant (P0.05) difference in total solid and protein content among study site. The fat content was significantly higher in sample from Welmera and samples collected from Debrezeit were significantly higher lactose, ash, and solid non-fat content. Specific gravity and freezing point were no significant difference among the four study site. Milk samples of significantly higher pH were observed in Wolmera and Selale and significantly higher titratable acidity was observed in milk samples from Sebeta. All the chemical composition of total solid, fat, protein, Ash, lactose and solid non-fat were fit with Ethiopian standard. Among the tested physical property-specific gravity and freezing point were fit with Ethiopian standard and titratable acidity of milk from all sites were above Ethiopian standard. PH of the samples from all locations was lower pH than Ethiopia standard. Titratable acidity was higher than Ethiopian standard and pH was lower than Ethiopian standard. This is an indication that the milk was not fresh and develop acid due to lactose fermenting microbes in the milk and not suitable for pasteurization or processing.