Newtonian and non-Newtonian food bolus behaviors obtained from validated swallowing simulator based on moving particle simulation

• Published in: FOOD SCIENCE AND TECHNOLOGY RESEARCH Vol. 29; no. 5; pp. 385 - 402
• Main Authors: Kamiya, Tetsu, Toyama, Yoshio, Hanyu, Keigo, Kikuchi, Takahiro, Michiwaki, Yukihiro
• Format: Journal Article
• Language: English
• Published: Tsukuba Japanese Society for Food Science and Technology 01.01.2023; The Japanese Society for Food Science and Technology; Japan Science and Technology Agency
• Subjects: degree of bolus coherence; Epiglottis; Esophagus; Flow rates; Flow velocity; Food; Mechanical properties; moving particle simulation; Newtonian fluid; Newtonian fluids; Non Newtonian fluids; non-Newtonian fluid; Rheological properties; Simulation; Swallowing; Tribology; validation; Velocity
• ISSN: 1344-6606; 1881-3984
• DOI: 10.3136/fstr.FSTR-D-23-00057

This study compared the behavior of food boluses describing Newtonian and non-Newtonian fluids through a validated human swallowing simulator based on moving particle simulation. The simulation was qualitatively and quantitatively validated through comparisons with videofluorography images. The positions and configurations of the food boluses and normalized brightness of the simulated and videofluorography images during every timestep were similar, and we thought that the simulator can be used to study the mechanism of food bolus behavior. The validated swallowing simulator results show that the key factors for the optimal design of the thickener are the control of the bolus inflow velocity, which is influenced by rheological and tribological properties, prevention of small splash particles, and bolus discharge flow rate from the epiglottis to the esophagus. In addition, we propose an evaluation index for the degree of bolus coherence based on the bolus flow rate and velocity.