Structure–function relationship of the milk fat globule
Résumé
Purpose of review
The complex biochemical composition and physical structure of the milk fat globule (MFG) are presented as
a basis for its paradoxical metabolic fate: MFG is a rapid conveyor of energy through its triacylglycerol
(TAG) core but contains some low-digestible bioactive complex lipids and proteins, which influence lipid
metabolism and contribute to intestinal and systemic health.
Recent findings
MFG structure modulates gastrointestinal lipolysis, postprandial lipemia and even the postprandial fate of
ingested fatty acids. Proof-of-concept of the nutritional programming induced by early consumption of an
emulsion biomimetic of MFG compared with a typical infant formula was published in an animal model
(mice). The metabolic response to a high-fat diet during adulthood was improved following neonatal
exposure to the biomimetic emulsion.
Summary
MFG TAG are tailored with a unique regiodistribution delivering in priority short to medium-chain fatty
acids in gastric phase, an important amount of quickly metabolizable oleic acid and protecting palmitic
acid in sn-2 position. MFG digestion may not only trigger rapid TAG and chylomicron plasma peaks with
fast clearance but also the luminal release of nonhydrolysable bioactive compounds (glycosylated
compounds and sphingomyelin), which contribute to intestinal and systemic health by shaping the
microbiota and modulating the immune system. These bioactive compounds form self-assembled structures,
protect specific micronutrients and lower cholesterol absorption. The health benefits of MFG consumption or
of some of its fractions (MFGM) under specific structures are steadily being demonstrated with still much
unsolved questions especially for populations with high nutritional needs (e.g. elderly, infants).