Impact of technological processes on buffalo and bovine milk fat crystallization behavior and milk fat globule membrane phospholipids profile

The effects of milk technological processes (pasteurization, homogenization, and freeze-drying) on the crystallization and melting behaviors of buffalo and bovine milk fat were investigated. As well, the profile of milk phospholipids was identified. Differential scanning calorimetry was used to evaluate the variations in the thermal behaviors of milk fat. Milk phospholipids were purified by the solid-phase extraction method, and then identified by using an ultra-performance liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry. Seven classes of phospholipids (including phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylglycerol, sphingomyelin, and lysophosphatidylcholine) were identified. Milk processing affected both the thermal characteristics and the profile of phospholipids, since the content of phosphatidylcholine increased after the homogenization of pasteurized milk. The finding of this study could provide a valuable knowledge to dairy industry and the related applications since it highlights the variations in milk fat crystallization and melting behaviors, and the profile of phospholipids throughout a series of technological treatments.