乳脂肪甘油三酯测定与分析方法研究进展

Research Progress on the Determination and Analysis Methods of Milk Fat Triacylglycerol

脂类是极其复杂多样的生物分子,仅已报道的乳脂肪甘油三酯(triacylglycerol,TAG)就达400多种,其中,乳脂中含量高于1%的近60种。目前液相色谱—质谱联用技术(liquid chromatography-mass spectrometry,LC-MS)是分离和鉴定TAG分子的主要手段,分离技术有反相高效液相色谱(reversed-phase high-performance liquid chromatography,RP-HPLC)、银离子高效液相色谱(silver ion high-performance liquid chromatography,Ag+-HPLC)、二维高效液相色谱(two-dimensional high-performance liquid chromatography,2D-HPLC)和超临界流体色谱(supercritical fluid chromatography,SFC),分子电离常用电喷雾电离(electrospray ionization,ESI)和大气压化学电离(atmospheric pressure chemical ionization,APCI)。质谱分析可以确定分子量和脂肪酸位置,但分子异构体鉴定仍面临挑战。我国针对牛、山羊、马、骆驼、牦牛和水牛等家畜的TAG缺乏系统研究。TAG谱的建立不仅可以评价乳脂肪的营养特征,指导饲养方式科学改进,也有助于建立物种、饲养方式、产地和加工方式的鉴定模型。对乳脂肪甘油三酯测定与分析方法的研究进展进行综述,以期为乳制品质量控制以及食品完整性和真实性鉴定提供理论依据。

Lipids are extremely complex and diverse biomolecules,and at least more than 400 types of milk fat triacylglycerol(TAG)have been reported.The content of nearly 60 reported types of TAG exceed 1%in milk fat.At present,liquid chromatography-mass spectrometry(LC-MS)is the commonly used method to separate and identify TAG molecules,including reversed-phase high-performance liquid chromatography(RP-HPLC),silver ion high-performance liquid chromatography(Ag+-HPLC),two-dimensional high-performance liquid chromatography(2D-HPLC),and supercritical fluid chromatography(SFC).Moreover,the mainly used molecular ionization methods are electrospray ionization(ESI)and atmospheric pressure chemical ionization(APCI).Mass spectrometry can determine molecular weight and fatty acid positions,but molecular isomer identification remains a challenge.Systematic researches on TAG for cattle,goats,horses,camels,yaks and buffalos are limited in China.The establishment of the TAG profile can not only evaluate the nutritional characteristics of milk fat and guide the scientific improvement of breeding methods,but also help to establish an identification model of species,breeding methods,origin and processing methods of milk.This article reviews the research progress on determination and analysis methods of milk fat triacylglycerol,in hoping to provide a theoretical basis for dairy product quality control as well as food integrity and authenticity identification.