The application of static digestive models simulating the digestion system of infants and young children for the development of accessory food: Current status and future perspective

Food digestion is a complex process. It is difficult to investigate the multiple stages in humans and animals, due to technical and ethical issues. Therefore, in-vitro digestive models have been a useful approach to understand the digestive dynamics of food that mimics the digestive process in the body. The human digestive system is age-dependent, especially in infants and young children. As the physiological situation of infants is immature, the growth and development processes are relatively complex and the conditions change rapidly with time, and thus the physiological parameters in the in-vitro digestive models of infants at different ages should be altered accordingly. However, there is currently no reported in-vitro digestion model that are designed closely according to the development state of the infants and young children. It is really necessary to develop such models for the design and development of accessory food for infants and young children, as they provide necessary nutrition for them. This study summarizes the impact of the state and types of food on the digestive system in infants and young children of different ages. When applying an in-vitro digestion model, researchers need to select appropriate parameters based on the liquid or solid state and nutrients content of different foods, as well as the physiological characteristics of the study population.