一步提取测定食品中的脂肪酸

Determination of fatty acids in foods by one-step extraction

建立了一步提取测定食品中脂肪酸的检测方法。乙酰氯与甲醇反应得到的盐酸-甲醇使试样中的脂肪和游离脂肪酸甲酯化,用甲苯提取后,氢火焰离子化检测器检测。各脂肪酸甲酯标准溶液在0.005～1mg/mL范围内呈线性相关(r=0.999);在不同基质中各脂肪酸回收率为82.1%～100%,相对标准偏差RSD<10%;各脂肪酸检出限为1mg/100g。一步提取测定脂肪酸操作方便、快速,灵密度高,可满足食品中脂肪酸测定的要求。

A method of one-step extraction determination of fatty acids in foods by gas chromatography（GC） was developed.Samples were esterified by hydrochloric acid-methanol, which was the reaction product of acetyl chloride and methanol.Extracting with toluene, contents of fatty acids were determined by GC with FID detector.The method had a good linear relativity（ r = 0.999）between 0.005-1 mg/mt Recovery rate in different samples range from 82.1% to 100%, RSD 〈 10% ,with the LOD of lmg/100g.With the advantages of easy-handling,fast and high sensitivity,one-step extraction method could meet the requirement of the determination of fatty acids in foods.