Milk protein and cheese yield in buffalo species

Abstract

Buffalo milk samples differing significantly for cheese yield values were analysed by 2D electrophoresis in order to outline a protein profile, with specific regards to k-casein fractions. Four buffaloes, two of which showing high cheese yield and two with low cheese yield selected from a group of 135 subjects were chosen for the proteomic analyses. Six main spots in 2D gels were recognized as αs1-, αs2-, β- and k-casein, α-lactoalbumin, β-lactoglobulin. The main visible differences in the 2D gels between buffaloes with high vs. low cheese yield were found in the appearance of the four k-casein spots (spots numbers:20, 19, 16, 18) which differ in the number of phosphorilation and glycosilation. The area and the intensity of the four spots were calculated by using Melanie II (Bio-Rad) software. Samples with high cheese yield showed higher value of the by-products: area x intensity of spot 16, correspondent to k-casein with one phosphorilation site, and lower values of spots 19 and 20, of k-casein with more than one phosphorilation site and glycosilated.