Abstract: In this research, the differences in protein and fatty acid composition among camel, cow and goat milks were analyzed by gel electrophoresis (GE) and gas chromatography (GC). The GE results showed that there were differences in the proportion of proteins in camel milk from different regions, and the production process had a significant effect on both camel milk protein and milk fat globule membrane protein composition. There were significant differences in protein composition among camel, cow and goat milks, and camel milk did not contain β-lacglobulin or αs1-casein, while cow and goat milks did not contain immunoglobulin G2 (IgG2) or IgG3. Therefore, GE could be used for the identification of camel milk mixed with cow or goat milk. The GC results showed that 31 fatty acids were detected in both camel and goat milks, and 29 fatty acids in cow milk. Camel milk contained fewer short-chain fatty acids than cow and goat milks, while the contents of most long-chain fatty acids were significantly higher than those in cow and goat milks. Principal component analysis (PCA) of the fatty acid composition data showed a clear separation of milks from different species and a clear discrimination between pure and adulterated camel milk. PCA can be used for the identification and analysis of fatty acids in camel milk mixed with cow milk and goat milk.

Key words: camel milk; gel electrophoresis; gas chromatography; protein; fatty acids