Regulating fat globule structure of infant formula based on MFGM to promote lipid uptake by improving lipolysis

Abstract

The digestive behavior and absorption properties of lipids are affected by differences in the interface structures of fat globules in human milk (HM) and infant formula. However, it is not clear how the interface changes of fat globules further regulate lipid uptake by improving lipid digestion. Based on the milk fat globule membrane (MFGM) and milk protein, two infant formula emulsions with different interface structures (F1: MFGM-stabilized emulsion, F2: whey protein and casein-stabilized emulsion) were prepared to simulate HM fat globules. The interface structure of lipid droplets, digestion behavior and absorption characteristic of lipids in infant formula emulsions were evaluated and compared with those of HM and commercial infant formula (IFM: supplied with MFGM). The results showed that MFGM-stabilized fat globules in F1 had a similar interface structure to HM. F1 could alleviate the coalescence and aggregation of lipid and protein in comparison with F2 and IFM. The order of triglyceride secretion from high to low was: HM (51.63 ± 2.0 μmol/L), F1 (45.19 ± 1.7 μmol/L), F2 (35.28 ± 1.3 μmol/L) and IFM (32.23 ± 1.3 μmol/L), indicating that HM and F1 exhibited faster lipid digestion and more chylomicron secretion. The expression of SLC27A4, FABP2, SCARB1, DGAT2, PLIN2, and MOGAT2 in HM and F1 was significantly higher than in F2 and IFM. Altogether, the simulation of HM fat globule at the interface structure based on MFGM could better promote cellular lipid uptake by influencing the digestion behavior of fat globules.