Lipidomics analysis for identifying the geographical origin and lactation stage of goat milk.

Goat milk samples of three lactation stages (colostrum, mature and late milk) were collected from three farms and analyzed with an untargeted method based on UPLC-Q-Exactive Orbitrap Mass Spectrometry and multivariate statistics. A total of 14 lipid subclasses and 756 lipid molecules were identified in samples. Five lipid subclasses and 51 lipid molecules in milk were significantly different among different geographical origins. Two lipid subclasses and 26 lipid molecules were significantly different among different lactation stages. Combined with the partial least squares discriminant analysis results of lipid molecules with a VIP value (Variable Importance in the projection) higher than 1, totally 38 and 19 lipid molecules could be used as potential indicators to identify geographical origins and lactation stages, respectively. Based on six and five selected molecules, the correct rates of discrimination models for geographical origin and lactation stage respectively reached 100% and 96%.