乳及乳制品中稳定碳同位素比的研究  

Detection of carbon isotope ratio of milk and dairy products

作　　者：张遴 王文瑞 李莹 

机构地区：[1]陕西出入境检验检疫局,西安710068

出　　处：《食品安全质量检测学报》2017年第11期4322-4326,共5页Journal of Food Safety and Quality

基　　金：国家质检总局科研项目(2016K213)~~

摘　　要：目的建立元素分析-稳定同位素比质谱法(elemental analyzer-isotope ratio mass spectrometry,EA-IRMS)测定乳及乳制品中δ^(13)C值的检测方法。方法本文研究了样品前处理、进样量、不同标样标定等对测定结果的影响,通过优化仪器工作条件,建立了稳定同位素比质谱仪测定乳及乳制品中碳同位素比(δ^(13)C)的方法,并用该方法对20余种品牌的乳及乳制品及3位哺乳期的母乳进行检测。结果研究数据表明,不同种类的乳汁δ^(13)C数值有明显差异:牛乳及其制品δ^(13)C值位于-16.50‰^-20.42‰,羊乳及其制品δ^(13)C值位于-22.38‰^-22.95‰,母乳δ^(13)C值为-23.17‰^-27.30‰。结论本方法根据羊乳和与牛乳δ^(13)C特征数值的差异,可以进行乳品纯正性判别。该方法精密度为0.04‰~0.24‰,小于常规0.3‰的要求,稳定性好、准确度高,操作简便,为乳及乳制品的鉴别提供了技术支持和理论基础。Objective To establish a method for analyzing the δ-（13）C in milk and dairy products by elemental analyzer-isotope ratio mass spectrometry（EA-IRMS）. Methods The influences of sample preparation, sample quantity and calibration of different standard samples were investigated. A stable isotope ratio（δ-（13）C） was established to determine the ratio of carbon isotope（δ-（13）C） in milk and dairy products by optimizing instrument working conditions. More than 20 kinds of milk, dairy products and 3 human milk in lactation period were tested by this method. Results The results indicated that, the δ-（13）C values had significant differences in different kinds of milk： liquid milk and its products were-16.50‰--20.42‰, goat milk and its products were-22.38‰--22.95‰, and breast milk were-23.17‰--27.30‰. Conclusion According to the difference in characteristic values of δ13^C in goat milk and milk, this method can distinguish the purity of milk and dairy products. The precisions of the method are 0.04‰-0.24‰, which are less than the regular requirement of 0.3‰. The established method has a good stability and reproducibility, and easy to operate, which can provide technical support and theoretical basis for identify milk and dairy products.

关 键 词：稳定同位素比质谱法 碳同位素比 牛乳 羊乳 母乳 

分 类 号：O657.63[理学—分析化学] TS252.7[理学—化学]