The Kanters Minigut Plus Platform microbial screening method allows for rapid and effective laboratory screening of effects of ingredients on a complex microbial flora, such as those in the gut. This in vitro screening method allows changes in the composition of the intestinal flora to become visible and thus gives a quick first impression of the mode of action of ingredients. The results provide clues for replacement of antibiotics in intensive farming, and may thus contribute to the prevention of antibiotic resistance.