基于GC-O-MS评价芽叶型黄茶的香气类型及其关键香气组分的呈香贡献  

Evaluation of Aroma Types and Key Aroma Components of Bud-leaf Type Yellow Tea Based on GC-O-MS

作　　者：周虹余 王瑗媛 李法鑫 聂枞宁 冯德建[3] 赵悦伶 杜晓[1] ZHOU Hongyu;WANG Yuanyuan;LI Faxin;NIE Congning;FENG Dejian;ZHAO Yueling;DU Xiao(Department of Tea Science,College of Horticulture,Sichuan Agricultural University,Chengdu 611130,China;Chengdu Academy of Agriculture and Forestry,Chengdu 611130,China;China Academy of Testing and Technology,Chengdu 610044,China)

机构地区：[1]四川农业大学园艺学院茶学系,四川成都611130 [2]成都市农林科学院,四川成都611130 [3]中国测试技术研究院,四川成都610044

出　　处：《茶叶科学》2024年第6期985-1004,共20页Journal of Tea Science

基　　金：雅安市创建国家现代农业产业科技创新中心“揭榜挂帅”项目(No.kczx2023-2025-04);茶叶标准与检测技术四川省重点实验室开放基金项目。

摘　　要：为全面探析芽叶型黄茶的特征香气成分,采用顶空固相微萃取(HS-SPME)结合气相色谱-质谱联用(GC-MS)和气相色谱-嗅觉(GC-O)技术,并辅以感官审评及化学计量学方法,对芽叶型黄茶香气物质进行分析。研究发现,芽叶型黄茶以清甜香为主,通过感官审评细分为鲜嫩香、栗甜香及甜香3类。利用GC-MS共检测到119种挥发性成分,并通过聚类分析(HCA)与正交偏最小二乘法判别分析(OPLS-DA)的变量投影重要性(VIP)筛选不同香型间的候选差异挥发物,采用相对香气活度值(ROAV)与GC-O分析明确了芽叶型黄茶的关键香气化合物。芽叶型黄茶有60种ROAV>1的特征香气成分,其中鲜嫩香型以醛类为主导,栗甜香型醇类占据主导,甜香型中2-乙基-5-甲基吡嗪与2,3-二乙基-5-甲基吡嗪贡献显著。嗅闻结果显示,苯乙醇是黄茶清甜香属性的重要成分;鲜嫩香的关键呈香物质包括苯乙醇、茉莉酮、苯乙烯、芳樟醇、壬醛等;栗甜香则主要来源于庚醛、β-大马士酮、2-正戊基呋喃等成分;甜香以吡嗪类与醛类为主,呈现出独特的甜香与焦糖香气。研究揭示了芽叶型黄茶香气成分的多样性,并深入阐明了各香型间的香气差异与成因。To comprehensively analyze the characteristic aroma components of bud-leaf type yellow tea,headspace solid-phase microextraction(HS-SPME)combined with gas chromatography-mass spectrometry(GC-MS),gas chromatography-olfactometry(GC-O),sensory evaluation and chemometrics were used to determine the aroma components of bud-leaf type yellow tea.It was found that the bud-leaf yellow tea was mainly characterized by a clear and sweet aroma,which was divided into three categories of“fresh-tender aroma”,“chestnut-sweet aroma”and“sweet aroma”by sensory evaluation.A total of 119 volatile components were detected by GC-MS,and then the candidate volatiles were screened out by the VIP values of cluster analysis(HCA)and orthogonal partial least squares discriminant analysis(OPLS-DA).Further,ROAV with GC-O analysis was used to clarify the key aroma components of bud-leaf type yellow tea.There were 60 characteristic aroma components with ROAV>1 in the bud-leaf type yellow tea,among which aldehydes dominated the“fresh-tender”type,alcohols dominated the“chestnut-sweet”type,2-ethyl-5-methylpyrazine and 2,3-diethyl-5-methylpyrazine contributed significantly to the“sweet”type.The olfactory validation indicates that phenylethanol was the most important component for the fresh and sweet aroma of yellow tea.The key aroma of“fresh-tender”included phenylethanol,jasmine ketone,styrene,linalool,nonanal.The“chestnut-sweet aroma”was mainly derived from the components of heptanal,β-damascenone and 2-n-pentylfuran,while the“sweet aroma”was dominated by pyrazines and aldehydes,which presented a unique sweet and caramelized aroma.This study reveals the diversity of aroma components in bud-leaf type yellow tea,and elucidates the aroma differences between aroma types and their causes.

关 键 词：芽叶型黄茶 香气属性 GC-O 关键香气成分 

分 类 号：S571.1[农业科学—茶叶生产加工] O657.63[农业科学—作物学]