对市售的11种品牌玉米油开展了脂肪酸（包括脂肪酸及其异构体）组成与含量的调查研究。采用气相色谱技术，结合主成分分析法，分析了不同品牌玉米油中脂肪酸的差异性和相关性。结果表明，11种品牌玉米油中共鉴定出19种脂肪酸，包括7种饱和脂肪酸，5种不饱和脂肪酸，6种反式脂肪酸（TFAs）和1种共轭亚油酸（t,t-CLAs），平均含量分别为14.18?10-2 g/g，80.32?10-2 g/g，1.47?10-2 g/g和0.23?10-2 g/g；其中，亚油酸（C18:2-9c12c）、油酸（C18:1-9c）和棕榈酸（C16:0）依次是玉米油中含量最多的3种脂肪酸；不同品牌玉米油中脂肪酸含量存在显著性差异（p<0.05）。主成分分析揭示了不同品牌玉米油在脂肪酸含量上的相似性、差异性及脂肪酸之间相关程度，TFAs和CLAs正相关程度高。本研究为评价市售玉米油脂肪酸品质特征提供了较为全面的数据支撑。

The composition and content of fatty acids and their isomers in 11 brands of commercial corn oil were investigated. The corn oils were analyzed by gas chromatography (GC) and the differences and correlations among fatty acids were assessed with principal component analysis (PCA). Nineteen types of fatty acids were identified in the 11 corn oil samples, including seven saturated fatty acids, five unsaturated fatty acids, six trans fatty acids (TFAs), and one conjugated linoleic acids (t,t-CLAs), with average content of (14.18, 80.32, 1.47, and 0.23)?10-2 g/g, respectively. Among them, the amount of linoleic acid (C18:2-9c12c) was the highest in corn oils, followed by oleic acid (C18:1-9c) and palmitic acid (C16:0). The fatty acid content varied significantly for different corn oil brands (p<0.05). PCA revealed similarities and differences of fatty acid content among the different brands of corn oil. The analysis also revealed correlations among fatty acids, in which a positive correlation between trans and conjugated fatty acids was identified. The study provides evidence to support the evaluation fatty acid quality in commercial corn oil.

国家自然科学基金项目（31271851）；北京市自然科学基金项目（6154033）；中国博士后基金项目（2014M561105，2015T80158）