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anglais. Recent findings have demonstrated that the food matrix structure is one of the key drivers to control the fate of food in the digestive tract and, consequently, the kinetics of nutrient release.As an example, using the pig as a model of human, we have demonstrated that, at identical composition, differences in dairy product macrostructure (milk vs acid or rennet gels) lead to differences in gastric emptying, protein hydrolysis in the gut and amino acid bioavailability. Compared to dairy gels, milk goes quickly through the stomach to reach the small intestine where protein will be rapidly and extensively degraded. This generates a fast and intense peak of plasma amino acids.When macrostructures are identical, differences at the microscopic scale can also have a strong impact on dairy product digestion. For instance, the structure of infant formula (IF) has been shown to dramatically influence the hydrolysis of milk protein. IF were designed at INRAE’s dairy platform and their in vivo digestion by piglets investigated. IF1 was a control IF with vegetable oil and milk proteins at the interface of the lipid droplet. In IF2, lipid droplets were stabilized by milk phospholipids in order to recreate a structure close to that of the milk fat globule. Finally, IF3 was also stabilized by milk phospholipids and 60% of the vegetable oil was replaced by milk fat. Piglets were fed 28d with one of the three IFs and then slaughtered. Concentration of milk proteins in the jejunum and ileum was higher for IF3 whereas IFN secretion was increased suggesting an improved intestinal immune system maturation such as observed in sow suckling piglets. Finally, the nature of IF was shown to drastically affect the intestinal microbiota composition of piglets. The structure of dairy products can therefore be considered as a lever to control the kinetics of nutrients release during digestion and fulfil the nutritional needs of specific populations such as elderly people, athletes, obese etc.