There has been a great deal of interest in adequately controlling digestibility of the ingested foods in the human digestive tract. Gastric digestion plays an important role in the process of food digestion, being strongly affected by both physical and chemical digestion processes. Over the last decade, the importance of in vitro gastric digestion models has been increasing, which is mainly attributed to superior applicability to various conditions as well as better reproducibility of experimental data. The authors developed a human gastric digestion simulator (GDS) that simplifies the antrum geometry and function. The major advantages of the GDS include quantitatively simulated gastric peristalsis and direct observation of the digestion behaviors of food particles in the gastric contents. In this review, we provide a brief overview of the findings obtained through a series of studies using the GDS. First, the current progress of in vitro gastric digestion studies is described. We next introduce the history and development of the GDS and findings on the digestion characteristics of representative foods and food models using the GDS. Further improvement of the GDS could potentially make it a useful tool for designing novel functional foods for which digestibility and release of nutrients and bioactives are well controlled.
