Composition and Characteristics of Goat Milk: Review 1968−1979

Abstract

Research in the past decade has extended knowledge of composition of goat milk and of properties of its constituents. Goats of several European breeds produce milk of lower fat content in the tropics than in temperate zones. Fat, protein, and lactose contents of milk of dwarf goats are higher than those of other breeds. Fat globules of goat milk resemble those of cow milk in lipid composition and properties of the globule membrane, but goat milk lacks "agglutinin" which causes fat globules of cow milk to cluster when cooled. Five principal proteins of goat milk, a-lactalbumin, 3-1actoglobulin, ~-casein, 3-casein, and as2-casein, closely resemble their homologs in cow milk. Goat milk lacks a homolog of bovine asl-casein, the most abundant protein in cow milk. Caseinate micelles of goat milk contain more calcium and inorganic phosphorus, are less solvated and less heat stable, and lose 3-casein more readily than bovine micelles. Activities of ribonuclease, lipase, and xanthine oxidase are less in goat than in cow milk. Goat milk contains more potassium and chloride but less orotic acid, N-acetyl neuraminic acid, folate, vitamin B6, and vitamin B12 than cow milk. Little work in the past decade has been on nutritive value of goat milk for humans except to describe cases of folate deficiency in infants.