多环芳烃在茶树鲜叶及绿茶加工过程中残留水平研究  

Residue Pattern of Polycyclic Aromatic Hydrocarbons in Tea Leaves during Green Tea Manufacturing Process

作　　者：高贯威 陈红平[1] 刘平香[1,2] 马桂岑[1] 郝振霞[1] 王晨[1] 柴云峰[1] 鲁成银[1] GAO Guanwei;CHEN Hongping;LIU Pingxiang;MA Guicen;HAO Zhenxia;WANG Chen;CHAI Yunfeng;LU Chengyin(Tea Research Institute, Chinese Academy of Agricultural Sciences, Tea Quality and Supervision Testing Center, Ministry of Agriculture R. P. China, Hangzhou 310008, China;Graduate School of Chinese Academy of Agricultural Sciences, Beijing 100081, China)

机构地区：[1]中国农业科学院茶叶研究所农业部茶叶产品质量安全风险评估实验室,浙江杭州310008 [2]中国农业科学院研究生院,北京100081

出　　处：《茶叶科学》2017年第2期191-200,共10页Journal of Tea Science

基　　金：中国农业科学院创新团队茶叶质量与风险评估团队(CAAS-ASTIP-2014-TRICAAS-06);浙江省公益应用项目(2017C32059);现代农业产业技术体系建设专项基金资助项目(nycytx-26)

摘　　要：利用气相色谱-串联质谱联用仪监测了茶树鲜叶及其绿茶加工中多环芳烃(PAHs)的残留水平。结果表明,不同地区茶树一芽二叶样品PAHs含量差异明显,产地环境PAHs污染程度对茶鲜叶PAHs含量影响较大。茶芽、嫩叶、老叶PAHs含量分别在40.5~52.8μg·kg^(-1)、50.0~67.4μg·kg^(-1)和91.5~97.6μg·kg^(-1)之间,PAHs含量大小顺序为老叶>嫩叶>芽。汽车尾气对交通公路旁茶树芽和嫩叶PAHs含量影响较大,且对50 m范围内茶树鲜叶影响更明显。电加热干燥模式下,水分散失和PAHs挥发是影响绿茶加工过程中PAHs含量的两个关键因子。加工环节过后,茶叶PAHs含量由61.0μg·kg^(-1)上升到166.1μg·kg^(-1)。摊放和干燥过程中PAHs大量挥发,造成茶叶干重中PAHs残留量由292.0μg·kg^(-1)降低到171.9μg·kg^(-1)。Residues of polycyclic aromatic hydrocarbons(PAHs)in fresh tea leaves and green tea duringmanufacturing process were determined by gas chromatography–tandem mass spectrometry.Results showed thatconsiderable variations of PAHs were identified in tea samples(a bud and two leaves)from different locations,indicating the contamination levels in the tea producing areas might significantly affect PAH residues in fresh tealeaves.The variations of PAHs contents in tea buds,tender leaves and mature leaves were40.5-52.8μg·kg-1,50.0-67.4μg·kg-1and91.5-97.6μg·kg-1,respectively.The order of PAHs contents follows as mature leaves>tenderleaves>tea buds.Vehicle exhaust was hypothesized to have a direct effect on PAH residues in tea buds and tenderleaves,as their levels were extremely high within50m around the roads.During the green tea manufacturing process,evaporation of moisture and PAHs by electric heating were the key factors affecting PAHs residues,which increasedfrom61.0μg·kg-1to166.1μg·kg-1in tea samples.Moreover,PAH residues might evaporate during the spreading anddrying processes,which decreased from292.0μg·kg-1to171.9μg·kg-1.

关 键 词：多环芳烃 汽车尾气 鲜叶 绿茶加工 残留水平 

分 类 号：TS272.4[农业科学—茶叶生产加工]