Dynamic gastric model (DGM)

Abstract

The Dynamic Gastric Model (DGM) was developed at the Institute of Food Research (Norwich, UK) to address the need for an in vitro model which could simulate both the biochemical and mechanical aspects of gastric digestion in a realistic time-dependent manner. As in the human stomach, masticated material is processed in functionally distinct zones: Within the fundus/main body of the DGM, gastric acid and enzyme secretions are introduced around the outside of the food bolus which is subjected to gentle, rhythmic massaging. Secretion rates adapt dynamically to the changing conditions within this compartment (acidification, fill state). Portions of gastric contents are then moved into the DGM antrum where they are subjected to physiological shear and grinding forces before ejection from the machine (and subsequent separate duodenal processing). The DGM has been used extensively for both food and pharmaceutical applications, to study, for example, release and bioaccessiblity of nutrients and drugs. The system allows the use of complex food matrices (as used in in vivo studies) and processes these under physiological conditions in real-time, thereby providing a realistic tool for the simulation of human gastric digestion.