State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi 214122, China.
State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi 214122, China.
Food Chem. 2019 Aug 15;289:616-624. doi: 10.1016/j.foodchem.2019.03.082. Epub 2019 Mar 18.
The quality of cooked rice and its influence factors have always been the focus of researches. However, the formative mechanisms of its eating quality and structural changes of rice during cooking have seldom been evaluated. In this study, sectional real-time cooking was performed by differential scanning calorimetry (DSC) and dynamic viscoelasticity analysis to monitor the phase transitions and mechanical changes of kernels, which exhibited different characteristics in different stages. Both glass transition and pasting behavior were captured, and showed more viscoelasticity of cooked rice at higher soaking temperatures. Meanwhile, the enzyme activity of rice during soaking was successfully measured by a rapid viscosity analyzer (RVA). Along with the differences of morphologies and crystalline structure at different soaking conditions, the findings of DSC and rheometer were further verified. This study provides effective methods to evaluate changes in rice during cooking and explains the mechanism of differences formed by the soaking temperature.
米饭的品质及其影响因素一直是研究的重点。然而，米饭食用品质的形成机制和煮饭过程中大米的结构变化却很少得到评估。本研究采用差示扫描量热法（DSC）和动态粘弹性分析进行分段实时煮饭，以监测颗粒的相变和机械变化，这些变化在不同阶段表现出不同的特征。玻璃化转变和糊化行为都被捕捉到了，并且在较高的浸泡温度下显示出了煮熟的米饭具有更高的粘弹性。同时，通过快速粘度分析仪（RVA）成功测量了大米在浸泡过程中的酶活性。结合不同浸泡条件下的形态和结晶结构差异，进一步验证了 DSC 和流变仪的结果。本研究为评估煮饭过程中大米的变化提供了有效的方法，并解释了浸泡温度形成差异的机制。
