毛细管气相色谱法测定鱼油食品中的脂肪酸DHA,EPA

Determination of DHA, EPA in Fish Oil Food by Capillary Gas Chromatography

采用毛细管气相色谱法测定鱼油中DHA和EPA的含量，色谱柱为DB-WAX型毛细管柱（30m×0．530mm,1．00μm），柱温采用程序升温，载气为氮气，流速15mL／min，FID检测器，温度为300℃，进样口温度260℃，分流比为10：1，进样量为1μL。DHA及EPA的质量浓度（X）分别在0．25-20．0，0．125～10．0mg／mL范围内与色谱峰面积（Y）呈良好的线性关系，线性方程分别为Y=90541X＋6060．6，Y=887335X＋4463．6，线性相关系数r均为0．9999，平均回收率分别为97．8％，96．1％，相对标准偏差小于3％（n=6）。该方法简便、重现性好，可用于鱼油中DHA和EPA含量测定。

The content of DHA and EPA in fish oil was determined by capillary gas chromatographic method. The chromatographic column was DB-WAX（30 m × 0.530mm, 1.00 μ m）. The column temperature was programmed . The carrier gas was nitrogen with the flow rate at 15 mL/min. The detector was FID and its temperature was 300℃. The injection temperature was 260℃, the split ratio was 10 ： 1, and the injection volume was 1 μL. The mass concentration of DHA methylester and EPA methylester was linear with peak area in the range of 0.25-20.0 mg / mL and 0.125-10.0 nag / mL respectively, the linear equation were Y=905 417X＋6 060.6, Y=887 335X＋4 463.6, and regression coefficient was 0.999 9. The average recovery were 97.8%, 96.1%, respectively, and the relative standard deviation was not more than 3% （n=6）. The method is simple and convenient, it can be used to determine the content of DHA and EPA fish oils with good accuracy and repeatability.