In this study, composite organogels containing sunflower seed oil were prepared with oryzanol/sitosterol and monoglycerides as gelators. The formation process of organogels and the influence of monoglycerides on the gelation process were examined. It was found that this process could be divided into three stages. Monoglycerides had little influence on the supercooling and supersaturatation stages. In the logarithmic stage of aggregation nucleation of gelators, monoglycerides could increase the enthalpy per unit volume and reduce the total Gibbs free energy, consequently promoting nucleation. In the linear stage of crystal growth and assembly, the primary, secondary and tertiary structures of organogels were gradually formed; the tertiary structure was most closely related to macroscopic properties and its ratio of permanent crosslinking to instantaneous crosslinking determined the main properties of organogels. Nuclear magnetic resonance analysis showed that the gelation process was mainly ascribed to physical entrapment. Furthermore, X-ray diffraction and small angle X-ray scattering were used to analyze the assembly structure and the results showed that a symmetrical hexagonal structure was found in oryzanol/sitosterol organogels, a symmetric layered structure in monoglycerides organogels, and composite organogels containing oryzanol/sitosterol and monoglycerides had a symmetric cubic structure.%以谷维素/谷甾醇和单甘酯为凝胶剂,葵花籽油为原料油制备复合凝胶油,探讨复合凝胶油的形成过程以及单甘酯对凝胶化过程的影响,实验发现凝胶油的形成可分为3 个阶段,在凝胶剂到达过冷、过饱和的平衡阶段,受单甘酯影响较小;在凝胶剂分子聚集成核的对数阶段,单甘酯会增加单位体积焓值,降低总吉布斯自由能,促进成核;而在晶体生长、组装的线性阶段,逐渐形成凝胶油的一级、二级、三级结构,其中三级结构与宏观特性最为紧密,三级结构中永久交联和瞬时交联的比例决定了凝胶油的主要性质.通过核磁分析表明物理截留油是凝胶化植物油的主要机理,在此基础性上通过X-射线衍射和小角X-射线散射分析了凝胶剂的组装结构,结果表明谷维素/谷甾醇凝胶油形成的为六边对称结构,单甘酯凝胶油形成的为层状对称结构,同时含有谷维素/谷甾醇和单甘酯的复合凝胶油为立方对称结构.
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