Seasonal Effect on Bovine Raw Milk Composition of Oulmes Local Race in Morocco

Abstract

A total of 120 samples were collected and examined in three seasons: autumn 2013, winter and spring 2014. The milk samples were obtained from Oulmes bovine race located in the Middle Atlas in Morocco. This search work aimed to characterize the physicochemical quality of this milk related to the different seasonal variations.

The physical parameters tested were, moisture, total solids, conductivity and freezing point. Also, some chemical components, including fat, protein, lactose, ash, density and the minerals (Ca, Mg, Na, K, P, Fe, Cu, Mn and Zn) were carried out. Protein, Ca and K levels demonstrated seasonal trends with a maximum of 3.66 ± 0.01%, 1476 ± 167%, and 1173 ± 179% respectively, in spring and conductivity of 4.35 ± 1.45mS in autumn, while minerals and many physical properties displayed considerable variations. Many significant interrelation ships in physicochemical properties were found mainly for protein which was strongly correlated to solid non fat (SNF) (r= 0.94), salts (r =0.75), density (r =0.80), lactose (r = 0.76), and freezing points (r =-0.69).

Keywords: bovine milk, Oulmes race, physicochemical composition, Pearson’s correlation.