基于"膜-核"结构探究米饭质构特性的形成机理OA

Most existing studies explore the mechanism of rice texture formation from the perspective of single component content and structural changes.In fact,the eating quality of cooked rice is determined by the structural characteristics of a"shell"formed by the leaching components and a"core"constituted by other components.This study modulates the"shell-core"structure of cooked rice by partially replacing the rice soup with hot water during the cooking process(at 5,10,and 15 minutes),and to investigate its effect on the textural properties of cooked rice.The results showed that as the leaching components were gradually replaced,the amylose-to-amylopectin ratio of the rice starch increased from 0.27 to 0.29～0.31,while the protein content showed no significant change.The rice flour consistently exhibited a clumpy structure,but with a gradual reduction in small surface fragments,and the starch became more prone to retrogradation.Scanning electron microscopy images of the cross-section of cooked rice revealed significant changes in the"shell-core"structure as the leaching components were replaced,manifested as a noticeable thinning of the"shell"structure and the internal porosity of the"core"gradually increases.The"shell"structure directly influences the adhesiveness between the rice and teeth,as well as between rice grains,and affects the stability of the"core"structure by influencing the heat and mass transfer rates.With the gradual replacement of the leaching components,the hardness of the cooked rice significantly increased,while the stickiness slightly decreased.In summary,the modifications in the"shell-core"structure significantly affect the compositional and physicochemical properties of cooked rice,thereby influencing its textural characteristics and providing theoretical guidance for precisely controlling the texture of rice to suit different populations and various processing requirements.