HPLC-ELSD与GC-MS法测定牛乳甘油三酯sn-2位脂肪酸组成  

Determination of sn-2 Fatty Acid in Triglyceride of Milk by HPLC-ELSD and GC-MS

作　　者：韩瑞丽[1] 马健 张佳程[1] 生庆海[3] 

机构地区：[1]青岛农业大学食品学院,山东青岛266109 [2]河北省乳业工程技术研究中心,河北石家庄050071 [3]东北农业大学黑龙江省乳品工业技术开发中心,东北哈尔滨150086

出　　处：《分析测试技术与仪器》2009年第1期30-34,共5页Analysis and Testing Technology and Instruments

摘　　要：研究建立了快速、准确测定牛乳脂肪甘油三酯sn-2位脂肪酸组成的方法.利用胰脂酶专一水解甘油三酯sn-1和sn-3位置上的脂肪酸得到sn-2单甘油酯和游离脂肪酸,再通过蒸发光散射高效液相色谱分离出sn-2位单甘油酯,然后对其进行衍生,用气相色谱质谱联用仪对sn-2脂肪酸组成进行分析.结果显示用蒸发光散射高效液相色谱法分离sn-2位单甘油酯时方法的回收率达到83.3%～85.1%,该法省去了传统测定中费时费力的薄层色谱分离步骤.用气相色谱质谱联用法对产物进行分析,精密度高,结果可靠.分析结果表明,牛乳脂肪sn-2位脂肪酸由2.57%月桂酸、7.68%豆蔻酸、34.74%棕榈酸、11.56%亚油酸、22.53%油酸和15.21%硬酯酸组成.A quick and sensitive method has been developed for the determination of the composition of sn - 2 fatty acid in milk fat. Free fatty acids and 2 - monoacyl - sn - glycerols were obtained from milk triglyceride upon hydrolysis of the acyl groups in the 1 - and 3 - positions of glycerol using porcine pancreatic lipase. Then 2 - monoacyl - sn - glyeerols was separated by high - performance liquid chromatography -evaporative light scattering detector（ HPLC -ELSD）, the 2 -position fatty acid composition was determined by gas chromatography and mass spectrometer（ GC - MS） of the fatty acid methyl esters. Results show that the recovery of the new method was 83.3% - 85.1%. This method eliminates the time -consuming thin -layer chromatographic separation procedure. It is accurate, rapid and simple for the determination of sn -2 fatty acids with GC - MS. The 2 - position fatty acids of milk are composed of C12H34O2 （2.57%）, C14H28O2 （7.68%）, C16H32O2 （34.74%）, C18H32O2 （ 11.56% ）, C18H32O2 （22.53%） and C18H36O2 （ 15.21% ） fatty acids.

关 键 词：牛乳脂肪 甘油三酯 sn-2位脂肪酸 蒸发光散射高效液相 气相色谱质谱联用 

分 类 号：O657.32[理学—分析化学]