菜籽油脂肪酸组成特征指标及大豆油掺伪后不合格判定的研究

对2011年至2013年全国592份油菜籽样品和我站近年来检测菜籽油的数据进行汇总分析。当菜籽油中掺入不同比列的大豆油时,采用气相色谱法与植物油油脂定性试验进行检测,比较气相色谱组分分析法与油脂定性试验的化学法的差异性,并对是否符合菜籽油脂肪酸组成进行判定。结果表明:从油菜籽提油脂肪酸组成数据分析得到:特征1:芥酸(C22∶1)与油酸(C18∶1)含量线性相关程度极高,用C22∶1对C18∶1作图得到两者线性方程Y=-1.112 02X+64.536 83,相关系数为R=-0.988 1,P0.001,有非常显著的统计学意义。特征2:92.39%菜籽油的棕榈酸(C16∶0)值不超过4.5%。特征3:99.06%正常菜籽油的亚油酸(C18∶2)范围在11.8%~20.3%。可利用这3项特征指标对菜籽油脂肪酸组成是否合格进行综合判定,较GB/T 5539—2008 4.7和GB/T 1536—2004判定方法,能有效降低掺伪检出限。

Study on rapeseeds oil fatty acid composition characteristic and adulteration research after mixed with different proportions of soybean oil

Review and analysis the rapeseeds extraction oil (main) fatty acid composition data from 2011 to 2013. Analysis rapeseed oil fatty acid composition data in recent years detection by our quality testing center. When rapeseed oil mixed with soybean oil, study the difference between the gas chromatography method detect to vegetable fats qualitative test method. The results showed that: Accumulated data from routine work and annual rapeseed census 2011 to 2013, from data analysis we find that: rapeseed fatty acid composition features 1: C22: 1 and C18: 1 content high degree of linear correlation, Correlation analysis revealed there was a positive correlation between the C22: 1 and C18:1, With C22: 1 to C18:1 mapping get the linear equation Y =-1.11202X 64.53683, correlation coefficient R = -0.9881, P <0.001, there were significant differences (p < 0.0001). Features 2: 92.39% normal rapeseed C16:0 value does not exceed 4.5%. Features 3: C18: 2 in the range of 11.8% ~ 20.3%. These three features can effectively reduce adulteration detection limit.