The cup aroma (CA), a lingering scent in the empty cup after tea consumption, is important to sensory evaluation and overall experience; however, the compounds contributing to the distinct floral honey-like CA of Fenghuang Dancong oolong tea (FHDC) remain unknown. CA of FHDC had strong nectar, ginger-like, and floral, while the tea infusion (TA) was characterized by tropical fruit, sweet, and floral notes. OAV and GC-O analyses revealed that esters, aldehydes, and alcohols were major contributors to the CA, with distinct variations in the volatile compound profiles between TA and CA. Twenty-one and 17 aroma active compounds were identified in TA and CA, respectively. GC-O analysis of the CA revealed 17 key odorants, among which α-ionone, geraniol, 4-methylpent-3-en-2-one, ( E )-2-nonenal, heptanal, limonene, linalool, and ( Z )-2-penten-1-ol exhibited intensities of 3 or higher. An aroma recombination experiments confirmed the identification of 17 key odorants, successfully replicating the original floral honey-like cup aroma.
Xia Yin,Yang-bo Xiao,Kuo-fei Wang,Rong-ji Tian,Ying-ying Shen,Han Tang,Run-long Wang,Shu-guang Zhang,Zhong-hua Liu
Shaking is a critical process for enhancing the aroma quality of black tea, though its molecular regulatory mechanisms remain unclear. Through integrated metabolomics and transcriptomics, we found shaking significantly intensifies floral-honey attributes, with a 30–50 % higher market value than conventional black tea.Stir bar sorptive extraction/gas chromatography-mass spectrometry (SBSE/GC-MS) analysis identified 11 key volatile compounds, including methyl jasmonate, jasmine lactone, indole, and nerolidol，as primary contributors to the characteristic aroma profile. The critical biosynthetic window was determined to be the shaking-to-withering transition phase (W8-W15). Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) coupled with transcriptomic analysis revealed that shaking activated lipid hydrolysis mediated by CsPLDα1 and CsGPAT , releasing linoleic acid and α-linolenic acid, which subsequently regulated the synthesis of methyl jasmonate and jasmine lactone through CsLOX-5 , CsOPR3 , and CsJMT . Additionally, the newly discovered CsTSβ1L-1 gene was implicated in potential cooperation with CsTSβ2 for indole biosynthesis regulation, while CsNES-1 and CsNES-5 were established as principal regulators of nerolidol synthesis.These findings collectively elucidate how shaking modulates the lipid, shikimate, and mevalonate pathways to shape black tea aroma, providing concrete molecular targets for industrial optimization of premium floral-honey aroma tea production.
危险品化学品经营许可证（带存储）