不同烘干方式对茶叶中稳定同位素特征及其产地溯源的影响  

Effects of Different Drying Techniques on Stable Isotopic Characteristics and Traceability of Tea

作　　者：刘志 张永志[1] 周铁锋[2] 邵圣枝[1] 周莉[1] 袁玉伟[1] LIU Zhi;ZHANG Yongzhi;ZHOU Tiefeng;SHAO Shengzhi;ZHOU Li;YUAN Yuwei(Key Laboratory of Information Traceability of Agricultural Products, Ministry of Agriculture / Institute of Quality andStandard for Agro-product, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021;Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021)

机构地区：[1]浙江省农业科学院农产品质量标准研究所/农业部农产品信息溯源重点实验室,浙江杭州310021 [2]杭州市农业科学研究院茶叶研究所,浙江杭州310021

出　　处：《核农学报》2018年第7期1408-1416,共9页Journal of Nuclear Agricultural Sciences

基　　金：公益性行业(农业)科研专项(201203046-2);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(2017)"

摘　　要：茶叶中稳定同位素特征检测和溯源技术是政府职能部门市场监管和保护地理标志产品的重要手段,为评估不同烘干方式对茶叶中稳定同位素特征的影响,考察茶叶产地溯源的有效性及判别模型的稳定性,本试验通过元素分析仪联用同位素比质谱(EA-IRMS)测定5种烘干方式(烘箱直接杀青烘干、微波杀青扁形机烘干、微波杀青烘箱烘干、扁形机杀青直接烘干和扁形机杀青摊晾烘干)下西湖龙井茶(龙井群体种)中4种稳定同位素比值(δ^(13)C、δ^(15)N、δ~2H和δ^(18)O),采用单因素方差分析(one-way ANOVA)和椭圆置信区间(EJCR)测试探讨不同烘干方式下西湖龙井茶中单个和多个稳定同位素比率的差异性。单因素方差分析结果表明,不同的烘干方式可能导致茶叶中单个稳定同位素比率出现较大变化,但多因素椭圆置信区间测试表明5种烘干方式西湖龙井茶间并不存在显著性差异。基于此,建立西湖龙井茶与山东、重庆产区茶叶δ^(13)C、δ^(15)N、δ~2H和δ^(18)O的线性判别分析(LDA)模型,2 000次随机循环,3个产区茶叶判别准确度均高达90.0%以上,充分验证了溯源的有效性及判别模型的稳定性。本研究结果为茶叶原产地保护提供了理论基础与应用可行性。The characterization of stable isotope and traceability technology of tea are important tools for government to regulate market and protect geographical indication. This study was aimed to evaluate the effects of drying techniques on the stable isotopic characteristics of tea, and investigate the feasibility of traceability and the stability of models. Fourstable isotopic ratios （δ^13C, δ^15N, δ^2H, δ^18O） in Westlake Longjing （WL） tea （Camellia sinensis cv longjingzhong）dried by five different drying techniques （direct fixation-drying in oven, fixation by microwave-drying in flat machine,fixation by microwave-drying in oven, fixation by flat machine-drying in oven, fixation by flat machine-sunning） were analyzed by elemental analyzer with isotope ratio mass spectrometry （EA-IRMS）. Then, one-way analysis of variance（ANOVA） and elliptical joint confidence region （EJCR） test were used to evaluate the difference of single and multiplestable isotopic ratio （ s ） between WL tea of five drying techniques, respectively. ANOVA indicated that dryingtechniques may significantly vary stable the isotope ratios in WL tea, but multi-factor EJCR test showed that there′s nosignificant difference between different drying techniques. Based on this, linear discriminant analysis （LDA） model ofδ^13C, δ^15N, δ^2H and δ^18O was established for the origin traceability of WL tea and tea from Shandong and Chongqing,in which the discriminant accuracies were up to 90.0% in 2000 times random runs, fully verifying the feasibility of origin traceability and the stability of discriminant model. The results which provides the theoretical basis and application feasibility for the protection of tea origin.

关 键 词：茶叶 烘干方式 产地溯源 稳定同位素 统计分析 

分 类 号：TS272.4[农业科学—茶叶生产加工]