Comparative evaluation of static and dynamic simulated digestion models.

Abstract

The digestion behavior of lipids plays a crucial role in their nutritional values. Currently, the complex dynamic variations of human gastrointestinal conditions are considered in simulated digestion models. The present study compared the digestion behavior of glycerol trilaurate (GTL), glycerol tripalmitate (GTP) and glycerol tristearate (GTS) in a static in vitro digestion model and a dynamic in vitro digestion model. In the dynamic digestion model, the parameters of gastric juice secretion, the rate of gastric emptying, the secretion of intestinal juice and the pH variations were estimated. The dynamic digestion model showed a certain extent of gastric lipase hydrolysis, while almost no lipolysis happened in the gastric phase of the static digestion model. A smoother digestive behavior was observed in the dynamic model than that in the static model. In the static model, the particle size distribution in gastric and intestinal phase changed rapidly in all triacylglycerol (TAG) groups. The change of particle size during the whole digestion period in GTL is more moderate than GTP and GTS. In addition, the final free fatty acids release degree was 58.558%, 54.36%, and 52.97% for GTL, GTP, and GTS, respectively. This study illustrated the different digestion profiles of TAGs in two digestion models and the results will contribute to a better understanding of different in vitro digestion models in lipid digestion. © 2023 Society of Chemical Industry.