Comprehensive analysis of species-specific differences in fatty acid composition and proteome of milk fat globules in human and animals.

Human milk, the gold standard for infant nutrition, precisely captures infant needs. This study analyzed the particle size distribution, fatty acid (FA) profile, and milk fat globule membrane (MFGM) proteome of milk fat globules (MFGs) in human milk and eight types of animal milks. Donkey and horse milks showed a greater abundance of smaller MFGs (0-5 μm). Human milk was richer in monounsaturated FAs, such as oleic acid and nervonic acid, whereas donkey had the most polyunsaturated FAs like linoleic acid and -11,14-eicosadienoic acid. Among the identified 1253 MFGM proteins, human milk showed significantly higher abundance of several novel immune enhancers including adiponectin B and vitronectin, antioxidases, and lipid metabolism regulators. Meanwhile, sheep milk and yak milk displayed greater abundance of zinc-α-2-glycoprotein and selenoprotein F, respectively. This study revealed physicochemical differences in MFGs between humans and eight types of animals, offering insights for improving animal-milk-based formulas for infants' nutritional needs.