In vitro digestion of food matrices and release of nutrients and microconstituents

The human body's use of the food it consumes begins with an essential stage: digestion. For ethical reasons, studies on humans and even animals are strictly regulated. As an alternative, in vitro systems have been developed.

There are currently two main distinctions between these systems: (i) static or batch systems, and (ii) dynamic systems.

Static and dynamic approaches are complementary, with the former making it possible to select food matrices, and the latter enabling certain digestion parameters to be taken into account more effectively, such as the kinetics of bolus acidification in the gastric compartment and the kinetics of digestive fluid intake and transfer between the different compartments.

Within the ISD team, we have these two types of device and a microfluidics device. We are involved in the activities of the INFOGEST international network on in vitro digestion of foods. We are also developing mathematical models and numerical simulations to study the role of parameters in the food matrix and digestive fluids.

We are particularly interested in the digestive fate of lipid dispersed systems containing the following compounds: lipids, proteins and liposoluble microconstituents (vitamins, carotenoids).

The research questions addressed are:

• How does the multi-scale organisation of nutrients within the food matrix impact nutrient release kinetics and bioaccessibility?
• What is the oxidative stability of lipids and microconstituents during digestion?
•  What is the impact of the composition and production process of proteinaceous plant raw materials on the digestibility and bioaccessibility of nutrients?