A review of in-vitro digestibility models on diverse foods in various segments of human digestive tract

Abstract In order to simulate the process of food digestion in the gastrointestinal (GI) tract, various in-vitro digestion models have been developed. These models vary from simple, single-compartment systems to more complex setups with multiple compartments and dynamic characteristics. In-vitro models have mostly been employed to analyze the structural changes and release of food components during digestion in different simulated gastrointestinal environments. The results obtained from in-vitro models of digestion differ significantly from those of in-vivo models because it is difficult to accurately replicate the highly intricate physiological and physiochemical processes occurring in the human digestive tract. The rate and location of food digestion in the gastrointestinal tract is considered very important for human health. However, this feat cannot often be realized for technical, ethical, or budgetary reasons. The significance of in-vitro models lies in their ability to provide reproducibility, the flexibility to select a controlled environment, and the simplicity of sampling. In-vitro models serve as valuable tools for conducting mechanistic investigations and testing hypotheses. This review provides a concise overview of in-vitro digestion models utilized for studying the digestion of different complex compounds that can predict the level of digestibility for a variety of foods. Digestibility models differ in predictability of digestibility. While some of them are designed more for controlled nutrient breakdown assessment, others more realistically mimic real life dynamic digestion.