基于脂肪酸组成特征的沙丁鱼油掺伪检测

为了解决鱼油原料市场日益突出的掺伪问题，本研究采用气相色谱法测定沙丁鱼及5种可能掺伪海水鱼的鱼油脂肪酸组成，并运用主成分分析（PCA）探究鱼油中各脂肪酸的变化规律，筛选出可能掺伪的海水鱼鱼油；运用偏最小二乘判别分析（PLS-DA）和多元逐步线性回归分析建立沙丁鱼油的掺伪鉴别模型。结果表明，5种鱼油与沙丁鱼油的脂肪酸组成有不同程度的差异，其中鳀鱼油与沙丁鱼油脂肪酸组成最为接近。PCA分析的总贡献率为89.8%，说明分析结果具有良好的代表性，鳀鱼油可以拟作沙丁鱼的掺伪油。PLS-DA分析认为沙丁鱼掺伪油的6种特征脂肪酸分别是二十碳五烯酸（EPA）、二十二碳六烯酸（DHA）、棕榈酸、棕榈油酸、二十二碳烯酸和油酸。沙丁鱼油掺伪鉴别模型所得相关系数（R2）分别为0.927、0.963、0.987、0.991，各模型平均误差分别为2.20%、1.38%、1.19%、0.83%，表明模型准确性较好。因此，该模型可实现鳀鱼油掺伪沙丁鱼油的定量识别，在鉴别沙丁鱼油掺伪上具有一定的可行性。

Adulteration Detection of Sardine Oil Based on Fatty Acid Composition Characteristics

In order to solve the increasingly prominent problem of adulteration in the fish oil raw material market， this study used gas chromatography to determine the fatty acid composition of sardine and five kinds of potentially adulterated marine fish. The variation pattern of each fatty acid in fish oil was investigated by examining its fatty acid composition and using principal component analysis （PCA） to screen out possible adulterated marine fish oil. The adulteration identification model of sardine oil was developed by using partial least squares discriminant analysis （PLS-DA） and multiple stepwise linear regression analysis. The results showed that the fatty acid compositions of five types of fish oil and sardine oil were different in varing degrees， among which anchovy oil and sardine oil were the closest. The total contribution of PCA analysis was 89.8% indicated that the analysis results were representative and anchoug oil could be proposed as adulterated oil of sardine. PLS-DA analysis showed that six characteristic fatty acids of sardine adulterated oil were eicosapentenoic acid (EPA) ，docosahexenoic acid （DHA)， palmitic acid， palmitoleic acid， docosenoic acid and oleic acid， respectively. The correlation coefficients R² of the sardine oil aduteration identification models were 0.927， 0.963， 0.987 and 0.991， and the average errors of the models were 2.20%， 1.38%， 1.19% and 0.83%， respectively， indicating the model had good accuracy. Therefore， this model can achieve quantitative identification of anchovy oil adulterated with fake sardine oil， and has certain feasibility in identifying adulterated sardine oil.