Coarse-grained dynamics simulation of the grain-filled structure of rice balls

Abstract

Rice is eaten as an aggregate of rice grains, and its perceived texture during oral processing changes with every chew. Mass production of rice balls with controllable food texture is still difficult because the relationship between the rice grain-packing structure and mechanical properties and food texture of rice balls is still unknown. This study aims to clarify the causal relationships between (1) the molding conditions of the rice ball and grain-filling structure, (2) the grain-filling structure and its texture, and (3) the mechanical properties of the rice ball and its texture. Using a rice grain-packing structure model which reflects the physical and chemical properties of the rice grains and balls in a coarse-grained dynamics simulation, changes in the packing structure during compression were observed, and the relationship between the rice grain-packing structure and mechanical properties of the rice balls was clarified. Furthermore, the behavior of rice grains during actual rice mass compression was successfully simulated using the developed rice grain-filling model. Our measurements and simulation results pave the way for an industrial method of producing rice balls with arbitrary food textures.