不同产地三文鱼的稳定同位素指纹特征及原产地溯源

Stable Isotope Fingerprinting of Salmon from Different Geographical Origins and Geographical Origin Traceability Analysis

本研究从深圳口岸获取我国三文鱼主要进口国(法罗群岛、挪威、智利、加拿大以及澳大利亚)的三文鱼样品共16份,并采集中国产三文鱼(虹鳟)样品2份,分析三文鱼肌肉、表皮、鳞片以及骨骼中的碳、氮、氢、氧、硫稳定同位素比值,比较不同产地以及不同部位同位素分布差异,采用判别分析对不同产地进行判别。三文鱼的碳、硫以及氢、氧稳定同位素具有显著的产地差异。不同组织之间同位素呈现明显的同位素分馏效应。鳞片以及表皮同位素比值对产地的指示效果优于肌肉和骨骼,结果表明采用稳定同位素能完全将以上产地的样品区分开,且还能将中国的虹鳟与进口的三文鱼进行区分。对市场随机购买的6份三文鱼样品的产地鉴别结果表明,稳定同位素技术能有效鉴别市场中三文鱼的产地造假行为,可用于对市场上三文鱼的产地追溯,以期为我国食品安全提供技术保障。

A total of 16 salmon samples from the major salmon exporters(Faroe Islands,Norway,Chile,Canada,and Australia)to China collected at Shenzhen Port,together with two rainbow trout samples produced in China,were analyzed for carbon,nitrogen,hydrogen,oxygen,sulfur stable isotope ratios in the muscle,skin,scales,and bones.The difference in isotopic distribution among tissues and geographical origins was compared.The discriminant analysis(DA)was employed for differentiating salmon from different geographical origins.There were significant differences in the isotopes of carbon,nitrogen,sulfur and hydrogen and oxygen among salmon from different geographical origins.Obvious isotopic fractionation effect was observed among different tissues.The scale and skin isotope ratios were more effective geographical origin indicators than the muscle and bone isotope ratios.The DA results showed that stable isotopes could be used to completely discriminate among the five geographical origins of salmon and also to distinguish Chinese rainbow trout from imported salmon.The geographical origins of six salmon samples randomly purchased from the market were successfully traced by the stable isotope technique. The method developed in this study can be used to trace the geographical origin of salmon products, which will provide technical support for ensuring food safety and consumer health.