LC/MS-based metabolomics to evaluate the milk composition of human, horse, goat and cow from China

Milk metabolites are associated with species of dairy animals and also affect the nutritional value of infant formulas. The objective of this study was to characterize the profile of milk metabolites between human milk and cow, horse, and goat milk, and identify any differences using non-targeted LC/MS metabolomic approaches, and analyze possible metabolic pathways. The results showed that 37 significantly different metabolites (P < 0.05 and VIP value > 1) were identified in the four milk samples. The metabolic pathways analysis revealed seven main metabolic pathways (P < 0.05 and pathway impact value > 0.1), including synthesis and degradation of ketone bodies, linoleic acid metabolism, arachidonic acid metabolism, pyruvate metabolism, inositol phosphate metabolism, alanine, aspartate, and glutamate metabolism and glycerophospholipid metabolism. These metabolic pathways could provide the data for the metabolism of dairy products in vivo. A better understanding of milk metabolites from different dairy animals could provide a rich reference to evaluate milk properties, and improve the quality of formulas and develop formulas closer to human milk.