In vitro mastication of cooked rice: How it influences the bolus characteristics

Abstract

AbstractBy the in vitro simulation of mastication, we studied the variation of cooked rice in terms of mastication parameters. However, because there is no in vitro model for cooked rice, it was impossible to specifically study the effect of mastication parameters on the properties of the rice bolus. Therefore, first we established an in vitro model, and then, we explored the effects of saliva addition, α‐amylase, and blending time on the physical properties of cooked Japonica rice in an in vitro simulation of mastication. The results showed that with the increasing saliva addition, the degree of lubrication, transverse relaxation time of free water (T23), and proportion of free water (A23) significantly increased, and the degree of structure, the elastic modulus (G′), and the viscous modulus (G″) of the bolus significantly decreased. With the increase of α‐amylase, the A23 significantly increased, and the degree of structure, G′, and G″ of the bolus significantly decreased. Increased blending times decreased the particle size of rice, resulting in the decrease of G′ and G″, while, A23 significantly increased, and the microstructure of the bolus became looser. Overall, the trends observed with different blending and different saliva addition models for simulated saliva fluid with 75 U/mL of α‐amylase were similar to those of an in vivo mastication model.Practical ApplicationsIn vitro simulation of oral processing depends on saliva composition, saliva addition, and the effect of salivary enzymes on food and food type. Therefore, through the in vitro simulating oral processing, we have been better studied the changes of sensory characteristics of rice with oral processing parameters. Thus, this study provides a simple, fast, and reproducible method for studying mastication's dynamic changes in rice's flavor, taste, and texture. Furthermore, this study provides a method for the in vitro mastication of rice and other foods. In addition, it offers scientific basis and theoretical reference for the variety improvement of Japonica rice and the quality improvement of instant rice.