Abstract
Limited studies have examined the effects of geography, climate, and lactation on mare's milk in Kazakhstan. The study aimed to assess the protein components and quality of mare's milk and koumiss from 24 mares in southern Kazakhstan. Milk samples were collected monthly between July and December 2023. The soluble protein fraction was analysed via SDS-PAGE. Casein fractions were examined using SDS-PAGE polyacrylamide electrophoresis. The results indicated the presence of α-, β-, and κ-caseins, along with whey proteins such as α-lactalbumin and β-lactoglobulin in the milk and fermented products. The milk contained 9.02% total solids, 1.62% protein and 1.22% casein on average. The mare milk fat content was 0.71% in Almaty, and in the Zhambyl region, it was significantly higher - 1.24%. The fermented koumiss products had a fat content of 1.22% in Almaty, while in Zhambyl, it was significantly higher at 1.94%. Similarly, the casein content in the Zhambyl region was 1.38%, compared to 0.81% in Almaty. The results indicate that different zones significantly affect mare's milk's fat and protein composition.