摘要
肉桂是武夷岩茶主栽品种,具有馥郁的花果香和辛锐的桂皮味特征。为明确武夷肉桂关键呈香物质和挥发性成分糖苷结合物(GBVs)对香气的贡献,采用超高效液相色谱四极杆/静电场轨道阱质谱仪系统(UHPLC-Q-Exactive/MS)和顶空固相微萃取-气相色谱-质谱联用(HS-SPME-GC-MS)技术对武夷肉桂加工过程GBVs和香气物质动态变化进行研究。结果表明,共检测到武夷肉桂11个不同加工阶段的276种香气物质,这些香气物质包括酯类、醇类、杂环化合物类、酮类、醛类、萜类等多种组分,其中杂环化合物类、酯类、萜类和醇类香气组分含量较高。正交偏最小二乘法判别分析(OPLS-DA)发现,武夷肉桂中30种特征香气物质变量重投影要性值和香气活度值均大于1,其中具有青味的(Z)-3-己烯醇和(E)-2-己烯醛含量在加工过程中下降,呈花香或果香的芳樟醇、苯甲醇、苯乙醛、香叶醇和β-罗勒烯含量在加工过程中上升,脱氢芳樟醇和α-石竹烯具有辛香的特征,可能是肉桂品种特征香气桂皮辛香的主要贡献物。在武夷肉桂毛茶中芳樟醇、苯乙醛、苯甲醇、2-乙氧基-3-甲基吡嗪和(E,E)-3,5-辛二烯-2-酮等物质香气特征影响值大于1,说明这些物质是武夷肉桂加工过程中关键呈香物质。在武夷肉桂中鉴定到10种GBVs,在加工过程中,葡萄糖苷的含量呈上升趋势,而樱草糖苷的含量呈下降趋势,GBVs总含量上保持相对稳定。在做青后期,葡萄糖苷和樱草糖苷的含量都呈现下降趋势,特别是苯甲基樱草糖苷、2-苯乙基樱草糖苷、香叶基樱草糖苷、芳樟基樱草糖苷和香叶基葡萄糖苷显著下降,结果表明GBVs参与了武夷肉桂花果香和甜香的形成。研究结果阐明武夷肉桂特征香气成分以及GBVs在武夷肉桂香气形成中的作用,有利于更好地提升武夷肉桂香气品质,提质增效。
‘Rougui’,the main cultivar of Wuyi rock tea,is characterized by a rich floral and pungent cinnamon aroma.To elucidate the contribution of key aroma constituents and glycosidically bound volatiles(GBVs)to Wuyi Rougui rock tea,this study employed ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF/MS)and headspace solid-phase microextraction-gas chromatography-mass spectrometry(HS-SPME-GC-MS)to investigate the dynamic changes of GBVs and aroma constituents during the processing of Wuyi Rougui rock tea.The results reveal that a total of 276 aroma constituents were identified from 11 different processing stages of Wuyi Rougui rock tea.These aroma constituents belong to various chemical classes,including esters,alcohols,heterocyclic constituents,ketones,aldehydes and terpenes,with heterocyclic constituents,esters,terpenes and alcohols being the predominant aroma components.Orthogonal partial least squares-discriminant analysis(OPLS-DA)identified 35 characteristic aroma constituents in Wuyi Rougui rock tea,as indicated by their Variable Importance in Projection(VIP)values and Odor Activity Values(OAV)greater than 1.Notably,the contents of constituents associated with green and grassy flavor,such as(Z)-3-hexen-1-ol,(E)-2-nonenal and hexanal,exhibited decreasing trends during the processing,while aroma constituents associated with floral or fruity aromas,like linalool,benzyl alcohol,benzaldehyde,eugenol and β-ocimene,displayed increasing trends.Furthermore,in fresh leaves of Wuyi Rougui rock tea,aroma constituents including linalool,benzyl alcohol,benzaldehyde,2-ethoxy-3-methylpyrazine and(E,E)-3,5-octadien-2-one exhibited ACI values greater than 1,suggesting they are key aroma constituents during the processing of Wuyi Rougui rock tea.Constituents such as dehydrocinnamyl alcohol andα-ionone contributed to the characteristic cinnamon aroma of Wuyi Rougui rock tea.In addition,ten GBVs were identified.During the processing,the contents of glucosides showed an upward tr
作者
吴宗杰
欧晓西
林宏政
余欣茹
程守悦
吴晴阳
李鑫磊
孙云
WU Zongjie;OU Xiaoxi;LIN Hongzheng;YU Xinru;CHEN Shouyue;WU Qingyang;LI Xinlei;SUN Yun(College of Horticulture,Fujian Agriculture and Forestry University,Fuzhou 350002,China;Key Laboratory of Tea Science of Fujian Universities,Fuzhou 350002,China;Tea Research Institute of Fujian Academy of Agricultural Sciences,Fuzhou 350012,China)
出处
《茶叶科学》
CAS
CSCD
北大核心
2024年第1期84-100,共17页
Journal of Tea Science
基金
国家茶叶产业技术体系(CARS-19)
福建农林大学茶产业链科技创新与服务体系建设项目(K1520005A06)
福建张天福茶叶发展基金会科技创新基金(FJZTF01)。
关键词
武夷肉桂
代谢组学
加工过程
香气
挥发性成分糖苷结合物
Wuyi Rougui rock tea
metabolomics
processing procedure
aroma
glycosidically bound volatiles
