不同放牧草地类型及畜种下羊肉脂肪酸指纹特征分析

Analysis of Fatty Acid Fingerprint Characteristics of Mutton Under Different Grazing Grassland Types and Livestock

为了建立一种畜种与肉品质特征关联的评价方法,从内蒙古阿拉善盟3个旗县采集羊肉样品132份,对其脂肪酸进行测定,并进行主成分分析(principal component analysis,PCA)。结果表明:(1)从不同生态类型的主成分分析结果来看,绵羊肉的沙漠类型与戈壁、山地类型可显著分离。沙漠类型的特征脂肪酸有顺-10-十七碳烯酸(C17:1),丘陵类型的特征脂肪酸有顺-9-十八碳烯酸(C18:1n9c)和二十烷酸(C20:0),戈壁类型的特征脂肪酸有十八酸(C18:0),山地类型的特征脂肪酸有十六烷酸(C16:0)。(2)由不同畜种的PCA结果可知,白绒山羊与蒙古羊羊肉可见显著分离。阿拉善白绒山羊的特征脂肪酸有C18:1n9c和顺-9-十六碳烯酸(C16:1),蒙古羊的特征脂肪酸有十四烷酸(C14:0)和C16:0。(3)不同部位的PCA结果得出,股二头肌与肋间脂肪部位羊肉样品可见显著分离。背最长肌的特征脂肪酸有顺-9-十六碳烯酸(C16:1)和顺-10-十七碳烯酸(C17:1),股二头肌的特征脂肪酸有C18:1n9c和α-亚麻酸(C18:3n3),肋间脂肪的特征脂肪酸有十四烷酸(C14:0)、十七烷酸(C17:0)和十八烷酸(C18:0)。由此可见,脂肪酸指纹特征可为阿拉善羊肉真实性判别提供新的思路和方法。

To explore an evaluation method for the relationship between varieties and meat quality,132 mutton samples were collected from three Banners of Alxa League in Inner Mongolia.The content of fatty acids in mutton was determined,and principal component analysis(PCA)was conducted.The results showed that(1)in terms of the PCA results of different ecological types,the mutton of desert type,the Gobi and the mountain types could be remarkably separated.The characteristic fatty acids are C17:1 for desert type,C18:1n9c and C20:0 for hilly type,C18:0 for Gobi type and C16:0 for mountain type.(2)PCA results of different livestock showed that there was significant separation between white cashmere goat and Mongolian sheep.The characteristic fatty acids of Alxa white cashmere goat are C18:1n9c and C16:1,and the characteristic fatty acids of Mongolian sheep are C14:0 and C16:0.(3)PCA results of different parts showed that there was significant separation between biceps femoris and intercostal fat.The characteristic fatty acids of longissimus dorsi muscle are C16:1 and C17:1,biceps femoris muscle are C18:1n9c and C18:3n3,intercostal fat are C14:0,C17:0 and C18:0.Therefore,fatty acid fingerprint characteristics can provide a new idea and method for the authenticity of Alxa mutton.