Preparation of liposomes from milk fat globule membrane phospholipids using a microfluidizer

The isolation of milk fat globule membrane (MFGM) material from buttermilk on a commercial scale has provided a new ingredient rich in phospholipids and sphingolipids. An MFGM-derived phospholipid fraction was used to produce liposomes via a high-pressure homogenizer (Microfluidizer). This technique does not require the use of solvents or detergents, and is suitable for use in the food industry. The liposome dispersion had an average hydrodynamic diameter of 95 nm, with a broad particle-size distribution. Increasing the number of passes through the Microfluidizer, increasing the pressure, or reducing the phospholipid concentration all resulted in a smaller average liposome diameter. Changing these variables did not have a significant effect on the polydispersity of the dispersion. Electron microscopy showed that the dispersions formed had a range of structures, including unilamellar, multilamellar, and multivesicular liposomes. The composition of the MFGM phospholipid material is different from that of the phospholipids usually used for liposome production in the pharmaceutical and cosmetic industries. The MFGM-derived fraction comprises approximately 25% sphingomyelin, and the fatty acids are primarily saturated and monounsaturated. These differences are likely to affect the properties of the liposomes produced from the phospholipid material, and it may be possible to exploit the unique composition of the MFGM phospholipid fraction in the delivery of bioactive ingredients in functional foods.