To date, most human gut microbiome research focusses on the colonic microbiome and less information is present regarding the ileum microbiome. Though, the ileum microbiome plays a prominent role in the immune system and human health. The difficulties and ethical restrictions regarding in vivo sampling oppose a need for relevant models. During this project an in vitro ileum microbiome model is developed in the SHIME, Simulator of the Human Intestinal Microbial Ecosystem, by adapting the nutritional medium, digestive secretions and colonization routes, followed by a validation to in vivo circumstances. Hereafter, insight in ileum dynamics by dietary carbohydrate modulation is obtained. The modulation compromises differences in carbohydrate load, composition and frequency. Finally, the ileum model is assessed to understand the ileum colonization ability in Crohn’s ileitis patients, possibly resulting in a standardized Crohn’s ileitis model.