摘要
为考察不同加工方式和样本制备目数对茶叶同位素分馏与测定的影响,建立茶叶中4种同位素δ13C、δ15N、δ2H、δ18O的元素分析-稳定同位素比率质谱(EA-IRMS)分析测试方法,研究红茶和绿茶加工过程中同位素分馏及不同目数样本制备的测试影响。结果表明,通过两点法或三点法构建的校准曲线具有很好的相关性,能够满足测试精度要求;相同原料所加工红茶和绿茶中4种同位素比率无显著差异,未发现同位素分馏效应;红茶和绿茶通过研磨后过80目、100目和120目筛与未过筛4种茶叶样品之间同位素比率无显著差异(P<0.05)。因此,相同原料的非发酵(绿茶)和发酵(红茶)加工以及不同目数样本制备对4种稳定同位素测定均无显著影响。本研究结果为茶叶稳定同位素数据库构建以及样品制备提供了方法基础。
In order to investigate the effect of different processing technology on isotopic fractionation and different mesh sizes on the delta value of bulk stable isotopes in black and green tea sample,an analytical method on element analyzer-stable isotope ratio mass spectrometry(EA-IRMS)of tea for stable isotope ratioδ13C,δ15N,δ2H,andδ18O was established.A good precision of analytical method was achieved using two-or three-point calibration.No significant difference was observed for the isotopic fractionation of four isotope ratios between black and green tea processing using the same leaves,and no significant difference was concluded using different mesh sieves(no sieving,80 mesh,100 mesh,120 mesh)on the effect of isotope ratios.Therefore,the tea-processing methods such as fermentation and sieving will not influence the isotopic fractionation results,which would provide a basis to establishment a tea data bank for the geographical traceability with different processing technology and for the pretreatment of plant sample before EA-IRMS.
作者
邵圣枝
聂晶
刘志
张永志
王钫
Karyne M.Rogers
袁玉伟
SHAO Shengzhi;NIE Jing;LIU Zhi;ZHANG Yongzhi;WANG Fang;Karyne M.ROGERS;YUAN Yuwei(Insititute of Quality and Sandards for Agriculural Products,Zhejiang Academy of Agriculural Science/Key Laboralory of Information Traceability for Agricultural Products,Ministry of Agriculture and Rural Affairs,Hangzhou Zhejang 310021;National Isotope Centre,GNS Science,30 Gracefield Road,Wellington Lower Hutt 5040,New Zealand)
出处
《核农学报》
CAS
CSCD
北大核心
2020年第1期78-84,共7页
Journal of Nuclear Agricultural Sciences
基金
浙江省农业科学院财政专项农产品信息识别与溯源技术研究与应用(2018).
关键词
茶叶
稳定同位素
加工
样品制备
tea
stable isotope
processing method
sample preparation
作者简介
邵圣枝,女,工程师,主要从事同位素检测与溯源技术研究。E-mail:shaoshenghi.ok@163.com;通讯作者:袁玉伟,男,研究员,主要从事农产品质量安全与溯源检测技术研究。E-mail:ywytea@163.com
