甘油酯体系低场核磁共振（LF-NMR）弛豫特性的研究有助于脂质重构进程的快速监测及产物分析.本文主要对不同酯化度的单一或混合油酸甘油酯体系的LF-NMR弛豫特性进行了研究.结果表明，油酸甘油酯呈现三个弛豫峰；随酯化程度增加或温度升高，单组分和多组分弛豫时间均增大，各峰面积比例有一定改变，且酯化程度越高，弛豫时间的变化幅度越大；对二元和三元油酸甘油酯体系而言，随三油酸甘油酯（GTO）比例增至40%，单组分和多组分弛豫时间均增大，S22峰面积比例增加，而S23减小；三元混合体系的LF-NMR弛豫特性经主成分分析（PCA）后，混合体系在得分图上随GTO比例及二油酸甘油酯/单油酸甘油酯配比（GDO/GMO）的变化而呈规律性分布.
Low field-nuclear magnetic resonance (LF-NMR) relaxation characteristics of glyceride mixture can be used in rapid monitoring and product analysis of lipid remodeling processes. In this study, the LF-NMR relaxation properties of single or mixed glyceryl oleate with different esterification degrees were studied. The results indicated that three peaks appeared in the T2 relaxation map of glyceryl oleate. With increasing esterification degree or temperature, both the single component and multi-component relaxation time increased, and the ratios of peak area changed as well. The higher the esterification degree was, the larger the relaxation time changed. For the binary or ternary mixed glyceryl oleate systems, with the glycerol trioleate (GTO) ratio increased to 40%, the single and multi-component relaxation time, the peak area proportion S22 all increased, while the peak area proportion S23 decreased. Principal components analysis (PCA) showed that the LF-NMR relaxation characteristics of ternary system had regular distribution on the score plot with changing GTO ratio and glycerol dioleate (GDO)/glycerol monooleate(GMO) ratio.
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