Lipidomic analysis of A1, A2, and heterozygous beta-casein genotypes in bovine milk using gas chromatography-mass spectrometry.

The consumption of A2 milk, which contains only the A2 type of beta-casein, has been increasing because it is considered healthier. In contrast, milk that contains the A1 type of beta-casein may cause gastrointestinal discomfort due to the release of the peptide beta-casomorphin-7 during digestion. The milk is composed of valuable proteins, liposoluble vitamins, and mineral salts, that could be essential source of dietary lipids for humans. The lipidomic analysis allows the characterization of important milk lipids. In this context, the objective of this work was to describe and determine the lipid profile and differential compounds in genotypes A1A1, A2A2, and A1A2 for beta-casein from bovine milk. Lipid extraction followed by gas chromatography coupled with mass spectrometry were performed on 54 bovine milk samples. As results, 12 differential metabolites were found, where the cholesterol; Cholesta-3,5-diene and Cholest-5-ene-3-ol(3. beta.)-carbonochloridate were the most abundant lipid compound in A2 milk. The identified lipids participate of the important pathways, such as the fatty acyl. The data obtained in this exploratory study provide insights into the main differences between the lipidomic profile of bovine milk present different beta-caseins in its composition.