【目的】探讨稳定性氢同位素在羊肉产地来源鉴别中的作用,为羊肉产地同位素溯源指标体系的确定和构建提供依据。【方法】利用稳定性同位素比率质谱仪(IRMS)测定来自内蒙古自治区锡林郭勒盟、阿拉善盟和呼伦贝尔市3个牧区,重庆市和山东省菏泽市2个农区脱脂羊肉中的δ2H值,通过方差分析和相关分析,探讨稳定性氢同位素组成的地域特征及其变化规律;结合C、N同位素指标,采用聚类分析及判别分析,进一步了解氢同位素在羊肉产地来源判别中的作用。【结果】不同地域来源羊肉中的δ2H值具有显著性差异,其δ2H值主要与当地饮水中的δ2H值高度相关。判别分析结果表明,δ2H值可使δ13C、δ15N指标对羊肉产地的正确判别率由80.8%提高到88.9%。【结论】稳定性氢同位素能够提供可靠的地域信息,可作为追溯和鉴定羊肉产地来源的一项有效指标。
【Objective】 Stable hydrogen isotope analysis was investigated for its potential in classification of lamb meat samples according to their geographical origins,aiming to provide a basis for the establishment of traceability indicator system of lamb meat in China.【Method】 The δ2H values of defatted lamb meat originating from three pastoral regions including Alxa League,Xilin Gol League and Hulunbuir City of Inner Mongolia,and two agricultural regions including Chongqing and Heze City were determined by Isotope Ratio Mass Spectrometry(IRMS).Analysis of variance(ANOVA) and correlation analysis were used to investigate the difference and the change of δ2H value in lamb meat depending on the geographical origin.Moreover,cluster analysis(CA) and discriminant analysis(DA) were applied to find out the role of hydrogen isotope in the discrimination of geographical origin of lamb meat combined with carbon and nitrogen isotopes.【Result】 There was a significant difference in δ2H value of defatted lamb meat from different regions,and the δ2H value in lamb meat was highly correlated with the δ2H value of their drinking water.The discriminant results showed that δ2H value could enhance the discrimination power of the combination of δ13C and δ15N for lamb meat,and the improved total correct classification rate was from 80.8% to 88.9%.【Conclusion】 The stable hydrogen isotope can provide reliable origin information and can be used to trace and authenticate the geographical origin of lamb meat.