Wang Lei, Wang Mengting, Lv Ruiling, Guo Mingming, Ye Xingqian, Ding Tian, Liu Donghong
College of Biosystems Engineering and Food Science, Zhejiang University Hangzhou 310058 China
Fuli Institute of Food Science, Zhejiang University Hangzhou 310058 China.
RSC Adv. 2019 Feb 13;9(10):5521-5529. doi: 10.1039/c8ra07790h. eCollection 2019 Feb 11.
In this study, we modeled the water absorption, softening and shear viscosity change kinetics of canned rice porridge during cooking as well as estimated the thermodynamic properties involved in hydration. Moreover, the internal microstructure of rice kernels was observed under different hydrothermal conditions. During cooking, the water absorption and shear viscosity alteration rate increased with temperature, whereas the softening rate decreased. However, the temperature did not significantly affect the equilibrium value of the physical properties. The variation tendencies of the moisture content and hardness of the kernels could be expressed satisfactorily by the exponential and the generalized exponential models. The porridge shear viscosity variations fitted the sigmoidal and its generalized models. Thermodynamic parameters (enthalpy, entropy and Gibbs free energy) revealed that the hydration process was non-spontaneous and exothermic. Furthermore, scanning electron microscopy images and the results of the X-ray diffraction analysis showed the microstructure of the kernels during cooking, and the kernels formed a homogeneous mesh structure at earlier times during the initial stage at higher temperatures. These findings would provide valuable information for the optimization of canned rice porridge production.
在本研究中，我们模拟了罐装米粥烹饪过程中的吸水、软化和剪切粘度变化动力学，并估算了水化过程中涉及的热力学性质。此外，还观察了不同水热条件下米粒的内部微观结构。烹饪过程中，吸水和剪切粘度变化率随温度升高而增加，而软化率则下降。然而，温度对物理性质的平衡值没有显著影响。米粒的水分含量和硬度变化趋势可以用指数模型和广义指数模型较好地表示。粥的剪切粘度变化符合S形及其广义模型。热力学参数（焓、熵和吉布斯自由能）表明，水化过程是非自发的且放热的。此外，扫描电子显微镜图像和X射线衍射分析结果显示了烹饪过程中米粒的微观结构，在较高温度下的初始阶段，米粒在较早时间形成了均匀的网状结构。这些发现将为罐装米粥生产的优化提供有价值的信息。
