绵羊脂与山羊脂品质特性差异分析Comparative analysis of quality and characteristics in sheep fat and goat fat

Abstract

旨在为羊脂的精深加工提供参考，以绵羊脂和山羊脂为研究对象，分析了两种羊脂理化性质、营养品质与风味特性的差异。两种羊脂的理化性质按国标方法测定，脂肪酸组成及胆固醇的含量由气相色谱测定，甘油三酯组成由超高效液相色谱联用Q-Exactive HFX高分辨轨道阱质谱仪测定，挥发性风味物质采用顶空-固相微萃取结合全二维气相色谱-飞行时间质谱法测定。结果表明：绵羊脂与山羊脂均检测出22种脂肪酸，主要脂肪酸均为C16∶ 0、C18∶ 1n-9c和C18∶ 0，饱和脂肪酸含量分别为38.69、54.39 g/100 g；两种羊脂均检测出30种甘油三酯，绵羊脂中三饱和、单不饱和、单饱和与三不饱和脂肪酸甘油三酯含量分别占总甘油三酯含量的2.66%、26.76%、36.89%和3369%，山羊脂的分别为15.87%、45.59%、26.47%和12.07%；绵羊脂与山羊脂鉴定出挥发性化合物共95种，含量分别为122.11、32.68 μg/g，关键风味化合物34种，其中癸醛、6-甲基-2-庚酮、乙酸戊酯、2-正丁基呋喃仅在绵羊脂中被检测出，3-甲基-2-戊酮仅在山羊脂中被检测出，主成分分析表明两种羊脂可完全分离，差异显著。综上，两种羊脂具有一定的品质差异，绵羊脂的营养与食用价值高于山羊脂，其特征风味强度显著高于山羊脂。 In order to provide a reference for the deep processing of mutton fat, the differences in physical and chemical properties, nutritional qualities and flavor characteristics of sheep fat and goat fat were investigated. The physical and chemical properties of two mutton fats were determined according to the national standard method. The content of fatty acids and cholesterol content were analyzed using gas chromatography. The composition of triglycerides of two mutton fats was evaluated by ultra performance liquid chromatography-Q-Exactive HFX orbitrap mass spectrometer. Furthermore, headspace-solid phase microextraction combined with comprehensive two dimensional gas chromatography-time of flight mass spectrometry was used to analyze the differences in volatile flavor compounds of two mutton fats. The results showed that 22 kinds of fatty acids were detected in two kinds of mutton fats, the main fatty acids were C16∶ 0, C18∶ 1n-9c and C18∶ 0. The content of saturated fatty acids of sheep fat and goat fat were 38.69 g/100 g and 54.39 g/100 g, respectively. Thirty kinds of triglycerides were detected in two mutton fats. The triglycerides of SSS, SSU, SUU and UUU in sheep fat accounted for 2.66%, 26.76%, 36.89% and 33.69%, respectively, and goat fat was 15.87%, 45.59%, 26.47% and 12.07%, respectively. The content of volatile compounds in sheep fat and goat fat were 122.11 μg/g and 32.68 μg/g, respectively. A total of 95 volatile compounds and 34 key aroma compounds were identified. Decanal, 6-methyl-2-heptanone, amyl acetate and 2-n-butyl furan were only detected in sheep fat, 3-methyl-2-pentanone was only detected in goat fat. The two kinds of mutton fats were completely separated by principal component analysis, which had significant difference. In conclusion, the two kinds of mutton fats have certain quality differences. The nutritional and edible value of sheep fat is higher than that of goat fat, and its characteristic flavor intensity is significantly higher than that of goat fat.

Keywords

• 绵羊脂；山羊脂；理化性质；脂肪酸；甘油三酯；挥发性物质
• sheep fat; goat fat; physical and chemical property; fatty acid; triglycerides; volatile compound