Effects of Pressure Soaking on Elastic Modulus of Steamed-Cooked Glutinous Rice Kernel

Abstract

The goal of this research is to assess the moduli of elasticity of steamed-cooked Thai Sanpatong 1 glutinous rice (GR) under various soaking conditions, primarily normal soaking and pressure soaking. The soaking process can influence properties of cooked rice. One of the main objectives is to determine the stiffness of cooked rice after soaking with either of the 2 methods, ASAE 368.4 was employed as main protocol for property testing and then Hooke’s and Hertz’s equations were used to estimate the moduli of elasticity. Poisson’s equation was used to estimate the Poisson’s ratios. The results show that the moduli of elasticity of the cooked normal-soaked and pressure-soaked rice determined using Hooke’s theory were 3.77 and 5.67 MPa, respectively. The moduli of elasticity of the cooked normal-soaked and pressure-soaked rice determined using Hertz’s theory were 1.58 and 2.33 MPa, respectively. Poisson’s ratio of the cooked normal-soaked and pressure-soaked rice were 0.27 and 0.28, respectively. Results revealed that the pressure treated rice has higher stiffness. HIGHLIGHTS Calculating modulus of elasticity of steamed-cooked Thai Sanpatong 1 Glutinous rice kernels obtained from Hertz’s theory yields get a higher modulus of elasticity than Hooke’s Theory Hertz's equation is suitable method to estimation of minimum and maximum values for radius of curvature of small grains Both of the modulus of elasticity calculated using these 2 theories theories reveal that the rice grains soaked under gauge pressure of 1 bar is stiffer than that ambient soaked GRAPHICAL ABSTRACT