基于多元统计方法不同性别玉树牦牛肉挥发性风味成分差异比较研究

Multivariate Statistical Analysis for Comparison of Volatile Flavor Components in Meat from Male and Female Yushu Yaks

为探究不同性别玉树牦牛肉挥发性风味物质的差异性成分,采用顶空固相微萃取与气相色谱-质谱联用技术鉴定挥发性成分,结合主成分分析(principal component analysis,PCA)、正交偏最小二乘判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA)和气味活度值(odor activity value,OAV)方法筛选不同性别玉树牦牛肉的关键差异风味化合物。结果表明:在玉树牦牛肉中共鉴定挥发性成分62种,共有组分54种,主要由醛类、醇类和烃类等化合物组成,其中醛类化合物是玉树牦牛肉的重要特征成分。比较不同性别玉树牦牛肉挥发性风味成分含量,母牦牛肉的风味品质更好。PCA筛选出11种化合物(辛醛、十六醛、2-乙基-1-己醇、十五醛、甲苯、壬醛、二乙二醇乙醚、1-辛醇、3-羟基-2-丁酮、反-2-辛烯-1醇、1-辛烯-3-醇)可作为不同性别玉树牦牛肉关键风味物质。OPLS-DA结合OAV筛选出5种化学成分(十六醛、壬醛、1-辛烯-3-醇、4-苯基-2-丁酮和2,3-戊二酮)作为不同性别玉树牦牛肉挥发性风味关键差异物质。

Headspace solid-phase microextraction(HS-SPME)and gas chromatography-mass spectrometry(GC-MS)were used to identify the volatile components of meat from male and female Yushu yaks.Furthermore,principal component analysis(PCA),orthogonal partial least squares discriminant analysis(OPLS-DA),and odor activity value(OAV)methods were used in combination to screen the key differential flavor compounds in male and female Yushu yak meats.A total of 62 volatile components identified,54 of which were common to both,the predominant ones being aldehydes,alcohols and hydrocarbons.Aldehydes were important characteristic components of Yushu yak meat.The comparison of the contents of volatile flavor components showed that the flavor quality of female yak meat was better.Octanal,hexadecanal,2-ethyl-1-hexanol,pentadecanal,toluene,nonanal,2-(2-ethoxyethoxy)ethanol,1-octanol,3-hydroxy-2-butanone,trans-2-octene-1-ol and 1-octene-3-ol were selected by PCA as the key flavor substances to discriminate between male and female Yushu yak meats.Hexadecanal,nonanal,1-octene-3-ol,4-phenyl-2-butanone and 2,3-pentanedione were selected by OPLS-DA combined with OAV as the differential key volatile flavor substances between male and female Yusu yak meats.