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 (acidifi cation, fi ll 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.

The Golden Egg: Nutritional Value, Bioactivities, and Emerging Benefits for Human Health

“…This remark suggests that the egg probably still encloses many unknown activities that merit further investigations considering the current lack of research assessing the fate of egg proteins along the digestive tract. Such studies could help to better appreciate the in vivo potential of egg proteins and of the resulting hydrolytic peptides, and could be easily apprehended using dynamic gastric models that have been used with other foodstuffs, in food- and pharmaceutically-based research [203,204]. These in vitro models mimic both the biochemical and mechanical aspects of gastric digestion.…”

In vitro and in vivo modeling of lipid bioaccessibility and digestion from almond muffins: The importance of the cell-wall barrier mechanism

“…Individual masticated AF ( n = 3) or AP ( n = 3) muffin samples (∼180 g each) were fed into the DGM for 63 min in the presence of priming acid (20 ml), whose composition has been reported previously ( Pitino et al, 2010 ). The digestion time was calculated by the in silico model associated with the DGM, based on the physico-chemical properties of the meal ( Thuenemann, Mandalari, Rich, & Faulks, 2015 ). The composition of the simulated gastric acid solution has been reported previously ( Mandalari et al, 2014 ).…”

Invited review: Dairy proteins and bioactive peptides: Modeling digestion and the intestinal barrier

“…Dynamic digestion models account for the different digestive secretions, which are added to the compartments of the model at specific time points. This addition can either follow a stable secretion rate (as for the simulated gastric juice in the human gastric simulator), it can follow a preprogrammed pattern (allowing the rate to change over time; e.g., in the TIM-1 model), or it can be programmed to change in response to other parameters, such as the volume of the model (e.g., gastric secretion in the dynamic gastric model; Thuenemann et al, 2015). Concerning dairy protein digestion evaluation, dynamic models have only been applied in few cases.…”