中文摘要：

[目的]探索稳定性同位素对中国牛肉产地溯源的可行性,了解牛不同组织中δ13C和δ15N指标在其中的作用.[方法]利用同位素比率质谱仪测定了来自吉林、贵州、宁夏、河北4个地域牛肉、牛尾毛、饲料中的δ13C和δ15N值,比较了不同地域牛组织中稳定性碳、氮同位素组成的差异,分析了各组织中同位素组成的相关关系,并结合牛的喂养方式,研究了δ^13C和δ^15N值的变化规律.[结果]不同地域牛组织中稳定性碳同位素组成有极显著差异,排序依次为吉林》贵州》宁夏》河北.吉林、宁夏两地样品与贵州、河北两地样品之间的δ^15N值有极显著差异,且后者高于前者.不同地域喂养牛的主饲料成分有其明显的地域特征.脱脂牛肉粉、粗脂肪、牛尾毛中碳、氮同位素之间呈极显著相关性.[结论]牛组织中δ^13C值可预测其膳食中C4植物所占的比例,δ^15N值可区分牧区与农区喂养的牛;δ^13C指标对牛肉产地来源的正确判别率高于δ^15N指标,两项指标相互补充可显著提高产地来源的正确判别率;脱脂牛肉粉、粗脂肪、牛尾毛中δ^13C、δ^15N值均可作为牛肉产地溯源的指标,它们对牛肉产地来源的判别规律一致.

英文摘要：

[Objective ] To assess the feasibility of isotopic traceability and function of δ^13C and δ^15N values in beef geographical traceability in China. [Method] The δ^13C and δ^15N values of beef, cattle hair and feeds collected from Jilin, Guizhou, Ningxia and Hebei were investigated with an isotope ratio spectrometer, the difference of carbon and nitrogen composition of beef samples from above four regions were compared and the correlations of isotope composition between cattle tissues were analyzed, furthermore, change of δ^13C and δ^15N values of beef samples under different feeding modes were also researched. [Result] The δ^13C values of cattle tissues from different regions showed significant difference in the order of Jilin〉Guizhou〉Ninxia〉Hebei. The δ^15N values of cattle tissues from Jilin and Ningxia were greatly significant lower than that from Guizhou and Hebei. The staple feeds from different regions had their own character. In addition, significant correlation was found in δ^13C and δ^15N values between defatted muscle, crude fat and cattle hair. [ Conclusion] The δ^13C values of cattle tissues was an effective index to predict the proportion of C4 plants in their feeds, and the δ^15N values could be used to discriminate the cattle feeding with grass from that with cereal. The identification rates for the cattle geographical traceability using δ^13C values were higher than that using δ^15N values, and the identification rates were improved both using the two indexes. The δ^13C and δ^15N values of defatted muscle, crude fat, cattle hair, which provided consistent information for geographical traceability, could be used in beef geographical origin assessment.