通过对河西肉牛西门塔尔和安格斯牛中脂肪酸成分测定，阐明两个品种间牛肉中脂肪酸的组成和特征差异。随机选取相同育肥方式的18个月龄发育健康的西门塔尔和安格斯公牛各9头，禁食12 h后进行屠宰，取背最长肌为样本，以气象色谱内标法对西门塔尔牛和安格斯牛肉中的脂肪酸组成及其含量进行测定，最后使用主成分分析法对两个品种牛肉脂肪酸的差异进行评价分析。2种牛肉中共鉴定出17种脂肪酸，包括5种饱和脂肪酸和12种不饱和脂肪酸，饱和脂肪酸中棕榈酸含量最高，分别为21.81%和23.54%，安格斯牛肉的不饱和脂肪酸含量比西门塔尔牛高7.10%，同时肉豆蔻脑酸、二十碳一烯酸、花生四烯酸及DHA 4种不饱和脂肪酸含量显著高于西门塔尔牛；基于主成分分析法提取7个核心脂肪酸为2种牛肉中的特征脂肪酸，建立综合数学模型F=0.590×F1+0.154×F2+0.124×F3，从脂肪酸组成及综合得分上来看，安格斯牛肉要优于西门塔尔牛肉。脂肪酸测定和主成分分析揭示了两种牛肉中脂肪酸组成的特征与差异，为河西优质牛肉产品的合理开发利用提供理论依据。

To research the difference of fatty acid composition between Simmental and Angus cattle in western area of yellow river, the content of fatty acid in samples was determined by gas chromatography and evaluated by principal component analysis. Nine Simmental bulls and nine Angus bulls were selected. All animals were provided the same diet and management. Nine bulls per breed at approximately 18 months of age were randomly selected and then slaughtered. Cattle were slaughtered after being fasted for 12 h. The fatty acid content of the longissimus dorsi muscle was measured. The results showed that 17 kinds of fatty acids were identified in the two kinds of cattle, including 5 saturated fatty acids and 12 unsaturated fatty acids. Among the saturated fatty acids, palmitic acid was the highest, which was 21.81% and 23.54% respectively. The content of unsaturated fatty acids in Angus beef was 7.10% higher than that in Simmental. The contents of four unsaturated fatty acids (myristic acid, eicosapeenoic acid, arachidonic acid and DHA) in Angus cattle were significantly higher than those in Simmental cattle. Based on principal component analysis, seven core fatty acids were extracted as the characteristic fatty acids in two kinds of cattle. A comprehensive mathematical model was established as F=0.590×F1+0.154×F2+ 0.124×F3. In terms of fatty acid composition and comprehensive score, Angus was better than Simmental cattle. Fatty acid determination and principal component analysis revealed the characteristics and differences of fatty acid composition in the two kinds of beef, which provided theoretical basis for the rational development and utilization of excellent beef cattle products in western area of yellow river.

甘肃省科技计划项目(18YFINA075)；甘肃省农科院重点研发计划项目（2020GAAS28）