Proteomic and lipidomic comparisons of milk fat globule membrane (MFGM) enriched ingredients from caprine and bovine buttermilk.

Milk fat globule membrane-enriched ingredients (MFGMi) have received increasing attention for its health-beneficial properties. This study compared protein and lipid composition of MFGMi prepared from bovine and caprine buttermilk using label-free proteomics and four-dimensional lipidomics. A total of 939 differential proteins and 258 differential polar lipids were identified. Proteomics showed a higher abundance of butyrophilin, host defense proteins and iron absorption proteins in caprine MFGMi, whereas bovine MFGMi contained more mucins and xanthine oxidase. Lipidomics showed a higher abundance of sphingomyelins, phosphatidylserines, arachidonic/docosapentaenoic acid-phospholipids (PLs) and plasmalogen-PLs in caprine MFGMi, whereas bovine MFGMi contained more phosphatidylcholines, and docosahexaenoic/eicosapentaenoic acid-PLs. Fatty acid profiling of PLs showed that caprine MFGMi contained more octanoic, capric, and linoleic acid, whereas bovine MFGMi contained more palmitic and myristic acid. Caprine MFGMi contained more ganglioside GD3(d38:1) and GD3(d40:1), whereas bovine MFGMi contained more GD3(d34:1). Perilipin-2 and PE(P-18:0/18:2) were characteristic biomarkers that distinguish bovine and caprine MFGMi.