Effects of the Type of Pectin and Concentration of Citric Acid on Digestive Behavior of a Bubble-containing Gel: Evaluation Using a Human Gastric Digestion Simulator

Recently, a new beverage was developed that forms a bubble-containing gel and expands in the stomach, so that it suppresses hunger despite being low in calories. In order to improve the hunger suppression effect of the beverage, it is important to clarify the optimum preparation conditions of the beverage so that it stretches the stomach wall to a larger extent, and for a longer time. Factors affecting the volume of a bubble-containing gel and its volume-retention capacity were investigated by in vitro digestibility evaluation using the human Gastric Digestion Simulator (GDS). It was determined that the degree of esterification of the pectin used and concentration of citric acid in the formulation affected the expansion volume of the gel immediately upon reaction with artificial gastric juice. Furthermore, the degree of amidation of the pectin used and physical properties of the gel also affected the retention capacity of the gel volume. For maximizing the expansion volume of the bubble-containing gel and its retention capacity after consumption of this beverage, it is necessary to consider the degree of esterification and amidation and the citric acid concentration in the formulation.