Effects of RBX oleogel and heat–moisture-treated rice flour in food matrices on digestibility and microbiota

Recently, oleogel and heat-moisture-treated (HMT) modified starch have gained much attention as a potential margarine replacement and a low-digestible starch, respectively. To date, most studies have investigated oleogel and HMT starch as individual components, while information regarding their physiological properties as a food matrix form is scarce. Here, we demonstrated that the HMT starch-oleogel food matrix exhibited the lowest plasma lipid and glucose levels, but high lipid and fecal excretion in mice, indicating that the food matrix possibly lowered lipid and carbohydrate digestibility. The resistant starch (RS) content was markedly decreased in the food matrix, suggesting other factors, such as lipid barriers and gel viscosity, in lowering the food-matrix digestibility. Roseburia, Adlercreutzia, and rc4-4 were enriched, while Bifidobacterium and Clostridium were reduced in the food matrix group. The present study provides insights into the in vivo physiological properties and the health benefits of oleogel and HMT starch in food matrix forms.