基于脂肪酸特征指标的鳕鱼肝油掺假鉴定  

Adulteration Identi?cation of Cod Liver Oils Based on Characteristic Fatty Acids

作　　者：王琼芬 郑平安 刘婷 张梦奇 WANG Qiongfen;ZHENG Ping’an;LIU Ting;ZHANG Mengqi(Zhoushan Institute for Food and Drug Control, Zhoushan 316021, China;Hailisheng Group Co. Ltd., Zhoushan 316021, China)

机构地区：[1]舟山市食品药品检验检测研究院,浙江舟山316021 [2]海力生集团有限公司,浙江舟山316021

出　　处：《食品科学》2019年第8期326-330,共5页Food Science

基　　金：浙江省食品药品监管系统科技计划项目(SP201627)

摘　　要：通过分析鳕鱼肝油中各脂肪酸的相对含量及特征指标变化规律,建立鳕鱼肝油掺假鱼油的鉴定方法。鳕鱼肝油中所含脂肪酸经柱前衍生转化为甲酯后进行气相色谱测定,采用面积归一化法计算各脂肪酸相对总脂肪酸的相对含量。根据多样本脂肪酸相对含量分析结果,找出能有效识别掺假的特征性指标二十二碳六烯酸(docosahexaenoic acid,DHA)/二十碳五烯酸(eicosapentaenoic acid,EPA)值和鲸蜡烯酸相对含量,并确定其限度范围,DHA/EPA值为1.40～1.68,鲸蜡烯酸相对含量为7.0%～9.4%。当鳕鱼肝油样品中测得的DHA/EPA值和(或)鲸蜡烯酸相对含量超过此限度时,可初步判定该样品掺假鱼油。为进一步有效识别掺假水平,本研究探索建立一种以DHA/EPA值和鲸蜡烯酸相对含量为坐标的掺假模型,并绘制不同掺假水平的识别分析图,46批样品经鉴定,有2批样品疑似掺假25%的鱼油。该鉴定方法准确可靠、直观简便,可用于鳕鱼肝油中掺假鱼油的快速鉴定。This study aimed to establish a method for identifying adulterated cod liver oils by analyzing the percentages of fatty acids in pure cod liver oil and the change of the characteristic fatty acids. The fatty acids in samples were methyl esterified by precolumn derivatization before being analyzed by gas chromatography (GC), and the percentage of each fatty acid in the total fatty acids was calculated by peak area normalization method. According to the results of multiple-sample analysis, the ratio of docosahexaenoic acid (DHA) to eicosapentaenoic acid (EPA) and the content of cetoleic acid were identified as the characteristic indexes for authentication, which were in the range from 1.40 to 1.68 and from 7.0% to 9.4% in pure cod liver oil. Adulteration of fish oil in cod liver oil samples could be determined when the characteristic indexes exceeded the ranges. A quantitative model for the level of adulteration of cod liver oil was established based on these characteristic indexes, and discriminant analysis was performed for different levels of adulteration. Out of 46 batches of samples examined, 2 were suspected to be adulterated with fish oil at about 25%. This method is accurate, reliable, simple and feasible and can be used for the rapid identification of adulterated cod liver oil.

关 键 词：鳕鱼肝油 鱼油 掺假鉴定 相对含量 DHA/EPA 鲸蜡烯酸 特征指标 

分 类 号：TS207.3[轻工技术与工程—食品科学]