3种不同类型藏羊的屠宰性能和肉品质的比较分析

Comparison of carcass and meat quality among three different types of Tibetan sheep

为评定3个不同类型藏羊屠宰性能、肌肉品质以及肌肉脂肪酸组成,本研究选取甘肃省甘南藏族自治州的欧拉、乔科和甘加3个类型成年公羊各6只(3周岁),屠宰后测定其屠宰性能、羊肉品质以及肌肉脂肪酸组成。结果表明,1)屠宰性能中,欧拉型藏羊、乔科型藏羊和甘加型藏羊的宰前活重、胴体重,屠宰率,板油重,板油/胴体重,背膘厚度,小肠重/宰前活重,瘤胃净重/宰前活重,大腿肌肉厚,腰部肌肉厚,左前躯骨重/胴体重均有极显著差异(P<0.01)。欧拉型藏羊的眼肌面积显著高于其他两种类型(P<0.05),欧拉型和乔科型藏羊的胴体长、肾脏重/胴体重显著高于甘加型(P<0.05)。甘加型和乔科型藏羊的左中躯肌肉重/胴体重显著高于欧拉型藏羊(P<0.05)。甘加型藏羊的左后躯骨重/胴体重的值显著高于乔科型藏羊(P<0.05)。2)不同类型藏羊肉色亮度,黄度以及总色差差异显著(P<0.05)。欧拉型和乔科型藏羊背最长肌的滴水损失极显著高于甘加型(P<0.01),甘加型藏羊背最长肌pH45min极显著高于欧拉型和乔科型(P<0.01)。3)3个不同类型藏羊肌肉中干物质、粗蛋白、粗脂肪和粗灰分的含量均无显著差异(P>0.05);4)欧拉型藏羊肌肉脂肪酸C18:0、C18:2trans、C18:2cis、C18:3及C20:5均显著高于乔科型(P<0.05),欧拉型和甘加型藏羊肌肉脂肪酸的C20:5极显著高于乔科型(P<0.01)。综上所述,3个类型藏羊中欧拉型和甘加型的屠宰率高于乔科羊,但甘加型藏羊的躯肌及躯骨更发达;3个类型藏羊肌肉的营养成分含量无显著差异;欧拉型藏羊肌肉的饱和脂肪酸及不饱和脂肪酸含量均高于乔科型藏羊和甘加型藏羊。

The objective of this study was to evaluate the slaughtering performance,meat quality,and muscle fatty acid composition of three different types of Tibetan sheep in Gannan,Gansu Province,which will provide a theoretical basis for the improvement of meat quality and breeding of fine varieties of Tibetan mutton.A total of 18,3-year old Oula,Ganjia,and Qiaoke Tibetan sheep(6 individuals for each type)were slaughtered to measure their slaughter performance,meat quality,and muscle fatty acid.The results showed that 1)The slaughter performance,body weight,carcass weight,slaughter rate,leaf fat,leaf fat/carcass weight,back fat thickness,small intestine weight/body weight,rumen net weight/body weight,thigh muscle thickness,lumbar muscle thickness and left forequarter bone weight/carcass weight of three types Tibetan sheep were extremely significantly different(P<0.01).The eye muscle area,carcass length,kidney weight/carcass weight of Oula sheep was higher than that of Ganjia sheep(P<0.05).The left trunk muscle weight/carcass weight of Ganjia and Qiaoke sheep was higher than Oula sheep(P<0.05).The left posterior bone weight/carcass weight of Ganjia sheep was higher than Qiaoke sheep(P<0.05).2)There were significant differences in lightness,yellowness andΔE among the three different types of Tibetan sheep(P<0.05).The water loss of the longissimus dorsi of Oula and Qiaoke sheep was much greater than that of Ganja sheep(P<0.01).The muscle pH45 min of Ganja sheep was much greater than that of Oula and Qiaoke sheep(P<0.01).3)There was no significant difference in dry matter,crude protein,crude fat,and crude ash content in the different types of Tibetan sheep muscles(P>0.05).4)The muscle fatty acid C18:0,C18:2 trans,C18:2 cis and C18:3 of Oula sheep were significantly higher than in Qiaoke sheep(P<0.05).The C20:5 of the muscle fatty acids of Oula and Ganja Tibetan sheep was extremely significantly higher than that of the Qiaoke sheep(P<0.01).From the above,the slaughter rate of Oula and Ganjia Tibetan sheep is better than that of Qiaoke,but the left muscle and left bone of Ganjia sheep were better,and there was no significant difference in the nutrient content of muscles of the three types of Tibetan sheep.In addition,the content of saturated fatty acids and unsaturated fatty acids in Oula muscle was higher than that of Qiaoke and Ganja sheep.