Protein composition of caprine milk fat globule membrane

Milk fat globule membrane proteins of individual goats were characterised using one-dimensional SDS-PAGE analysis. Many differences were observed between bulked caprine and bovine milk samples. Goat sample showed much higher content of xanthine oxidase and of minor proteins compared with cow sample. Among individuals, a high heterogeneity could be observed; 32 bands were identified of which 19 were present in all caprine samples. Several previously non-described bands were detected. No correlations between fat content of milk, average size of fat globules and total protein of washed creams were observed. However, both the amount of protein and the correlations among them could be linked to their physiological role, i.e., general or specific transport, cell signalling, metabolism and immune functions.