Towards infant formula biomimetic of human milk structure and digestive behaviour

Abstract

-Lipids of human milk or infant formula convey most of the energy necessary to support the newborn growth. Until recently, infant formula chemical composition had been optimized but not their structure. And yet, more and more proofs of evidence have shown that lipids structure in human milk modulates digestion kinetics and is involved in metabolic programming. Indeed there is a striking difference of structure between human milk which is an emulsion based on dispersed milk fat globules (4 mm) secreted by the mammary gland and submicronic neoformed lipid droplets (0.5 mm) found in infant formula. These droplets result from a series of operation units. This difference of structure modifies digestion kinetics and emulsion disintegration in the intestinal tract of the newborn. This difference persists along gastric phase which is mainly dominated by acid and enzyme-induced aggregation. Lipid droplets size is thus the key parameter to control gastric lipolysis and emptying and intestinal lipolysis. This parameter also controls proteolysis since adsorbed proteins are more rapidly hydrolyzed than when in solution. In animal models, these differences of lipid structure would also impact digestive and immune systems' maturation and microbiota. Lipid structure during neonatal period would also be involved in the early programming of adipose tissues and metabolism. The supplementation of infant formulas with bovine milk fractions (milk fat globule membrane extracts, triacylglycerol) or recent development of large droplets infant formula, along with new fields of innovation in neonatal nutrition, are here reviewed.Keywords: human milk fat globules / lipid structure / infant formula / neonatal digestion / programming Résumé -Vers des formules infantiles mimant la structure et le profil de digestion du lait maternel.Les lipides laitiers du lait maternel ou de formules infantiles fournissent la plupart de l'énergie disponible pour la croissance du nouveau-né. Jusqu'alors, la composition chimique des formules infantiles a été optimisée mais pas leur structure. Or il est de plus en plus démontré que la structure des lipides dans le lait maternel module les cinétiques de digestion et participe à la pré-programmation métabolique. Il existe en effet une différence majeure entre les émulsions natives de globules gras laitiers (4 mm) sécrétées par la glande mammaire et la structure des lipides dans les formules infantiles qui résultent d'une succession d'opérations unitaires de transformation et sont constituées de gouttelettes submicroniques (0.5 mm) avec des interfaces néoformées. Cette différence de structure modifie les cinétiques de digestion et de déstructuration des émulsions dans le tractus digestif des nouveau-nés. De façon générale, la différence de structure initiale entre lait maternel et formules infantiles se maintient pendant toute la phase gastrique, qui est surtout dominée par des mécanismes d'agrégation acide et enzymatique. La taille des gouttelettes est le paramètre clé pour contrôler les lipolyses gastri...

Plant‐based Milks: A Review of the Science Underpinning Their Design, Fabrication, and Performance

“…Evolutionary pressures have designed milk to be an excellent source of macronutrients and micronutrients for the growing infant, which provides it with some unique features (Bourlieu et al, 2018;Le Huerou-Luron, Lemaire, & Blat, 2018;Lee et al, 2018). The milk fat globule membrane (MFGM) in raw bovine milk contains components (lipids, proteins, and carbohydrates) that are believed to interact with the gut microbiome of the growing infant (Bourlieu et al, 2017). In addition, bovine milk contains various kinds of oligosaccharides that can also promote the establishment of a healthy gut microbiome (Oliveira, Wilbey, Grandison, & Roseiro, 2015;Robinson, 2019).…”

Lipid Composition and State of Oxidation of Fortified Infant Flours in Low‐Income Countries Are Not Optimal and Strongly Affected by the Time of Storage

“…Globally, 6/ 3 ratios were high in fortified FI and sometimes excessive compared to the recommended range (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15). Furthermore, the amounts of essential FA (linoleic acid C 18:2 n-6 and -linolenic acid C 18:3 n-3) present in the FI were sometimes too high.…”

“…[4,10] Indeed, lipids play several important functions for young children, as they supply most of the calories necessary for growth and contribute to the development of cerebral functions and to lipophilic vitamin transport. FI are used in complement to breastfeeding from the age of 6 months, in the form of gruel or porridge, consumed on a daily basis.…”

Nutritional programming in early life: the role of dietary lipid quality for future health

“…In contrast, the lipid composition in Infant Milk Formula (IMF) is maintained constant and uniform to adhere to (inter)national legislation (see EU Commission Directive, 2006) (Innis, 1992(Innis, , 2007Koletzko et al, 2005). IMF encompasses small lipid globules triglycerides with milk proteins adhering to the globule surface and the majority of the lipid content is comprised of triglycerides (Gallier et al, 2015;Bourlieu et al, 2017).…”