分子蒸馏单甘酯对谷维素-谷甾醇凝胶油结构和性质的影响

以精炼葵花籽油为基料油,添加分子蒸馏单甘酯与谷维素-谷甾醇制备复合凝胶油,探讨凝胶剂分子间比例对凝胶油结构和性质的影响,以分析单甘酯在复合凝胶油形成过程中的作用。结果表明:在复合凝胶油中单甘酯会与谷甾醇存在着范德华力等弱的非氢键作用力,使得单甘酯和谷甾醇在临界凝胶浓度下,协同形成复合凝胶油。单甘酯的添加对复合凝胶油热力学性质和流变学性质等宏观特性均产生较大影响,添加单甘酯后复合凝胶油微观结构和红外光谱产生了显著变化,随着单甘酯含量的增加,氢键作用逐渐减小直至消失,而微观结构由纤维网状到球状结晶最后为针状结晶;结果还表明添加单甘酯后凝胶油氧化更慢,利于长期贮藏。

Influence of Distilled Monoglycerides on the Structure and Property of γ-Oryzanol and β-Sitosterol Organogel

In this study, composite organogels were prepared from refined sunflower oil as base oil added with monoglycerides, oryzanol and sitosterol. The effect of gelator ratio on the structure and property of organogels were examined to analyze the role of monoglycerides in the formation of composite organogels. Results showed that the weak non-hydrogen bonding forces between monoglycerides and sitosterol, such as Van der Waals force, structured sunflower oil to form composite organogels under their critical gel concentration. It was also found that monoglycerides had great influence on thermodynamic properties and rheological properties of composite organogels. The microscopic structure and infrared spectra were significantly changed with the addition of monoglycerides. With the increase of monoglycerides content, the hydrogen bonding forces gradually diminished and finally disappeared. The microstructure was changed from fibrous network to spheroidal and finally needle-shaped crystal. The results also showed that the oxidation of organogels was slower with the addition of monoglycerides.