【摘要】 用4种工艺制作米饭,用质构仪测定米饭的应力松弛曲线,并分析米饭的主要化学成分,研究米饭的应力松弛参数与化学成分的关系,为米饭蒸煮工艺的优化和新型炊具的开发提供基础数据。结果表明,不同工艺蒸煮的米饭的应力松弛参数有较大的差异性,较低温度下蒸煮的米饭的硬度较大,较高温度下蒸煮米饭的黏性较大。米饭的平衡弹性系数E0为15.754~89.323Pa;衰减弹性系数E1为34887.528~35213.051Pa;松弛时间τ为0.130~0.179s;松弛非线性指数n为0.019~0.054,黏度系数η为4538.085~6248.998Pa.s。米饭为具有一定交联程度的黏弹性体,其松弛参数与米饭的化学成分有较大关系,蛋白质含量较高的米饭的E0、τ和η较大;脂肪含量较高的米饭的E0较小;直链淀粉含量较高的米饭的E1和τ较小。建立的基于米饭的化学成分与米饭松弛参数的多元幂函数式方程具有较高的拟合精度。更多还原

【Abstract】 Stress relaxation curves of cooked rice prepared by four cooking technologies were determined with texture analyzer and major chemical components of cooked rice were also measured. The relationship between stress-relaxation parameters and chemical components were studied in order to offer parameters for technology optimization and new cooker development. Obvious difference of stress-relaxation property could be obtained from cooked rice prepared by different cooking technologies. Cooked rice had higher hardness when rice was cooked at lower temperature. When cooked at higher temperature, cooked rice exhibited higher viscosity. The equilibrium elastic modulus E0, retarded elastic modulus E1, relaxation time τ, nonlinear exponential n and viscosity coefficient η of cooked rice were 15.754~89.323 Pa, 34887.528~35213.051 Pa, 0.130~0.179 s, 0.019~0.054 and 4538.085~6248.998 Pa·s, respectively. Cooked rice presented cross-linking viscoelastic behavior whose stress-relaxation parameters were related to its chemical components. Higher protein content resulted in higher E0, τ and η of cooked rice. Cooked rice with higher fat content had smaller E0 and with higher BV had smaller E1 and τ. The stress-relaxation parameters of cooked rice could be well described by the multivariate power function models based on chemical components of cooked rice.更多还原