不同的不饱和脂肪酸各自具有其不同的生理功能,但常见的不饱和脂肪酸产品大部分为几种脂肪酸的混合物,故在应用前对不纯的脂肪酸产品进行组成分析是必须的。测量了不饱和脂肪酸产品组分中最常见的油酸和亚油酸的拉曼光谱,确定了各拉曼谱线的振动模归属,分析了其分子的构象特征。该结果为研究长链不饱和脂肪酸的振动能级结构及能级间跃迁等做了基础工作,丰富了有机物分子的价键数据和性质。同时详细分析比较了油酸和亚油酸拉曼光谱的差异,为定性鉴别脂肪酸产品的成分提供了一种简便有效的方法,对拉曼光谱在地沟油检测方面的应用具有重要的指导意义。
Different unsaturated fatty acids have different physiological functions, however, the common fatty acid products are mostly mixture of several unsaturated fatty acids. Thus it is necessary to analyze the compo- sition of impure fatty acid products before application. In the present article, the Raman spectra of oleic acid and linoleic acid (the most commonly appearing components of fatty acid products) were measured. Further- more, the mode assignments of the Raman bands were determined and the molecular conformational characters were analyzed. The results lay the groundwork for researching the energy level structures and transitions of long-chain unsaturated fatty acids and enrich the valence bond data of organic molecules. In addition, the differences between the Raman spectra of oleic acid and linoleic acid were analyzed in detail, which provides a convenient and effective method for their identification and has directive significance for the application of Raman spectroscopy in hogwash oil detection.