Aged fragrance formed during the post-fermentation process of dark tea at an industrial scale. (16th April 2021)

• Record Type: Journal Article
• Authors: Zhang, Huan; Wang, Jiajia; Zhang, Dandan; Zeng, Li; Liu, Yanan; Zhu, Wen; Lei, Gaixiang; Huang, Youyi
• Is Part Of: Food chemistry. Volume 342(2021)
• Publication Date: 2021-04-16
• Subjects: Qingzhuan tea -- Volatiles -- Aged fragrance -- Pile-fermentation -- Aging storage; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2020.128175
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Analysis of volatiles responsible for aged fragrance in post-fermentation of dark tea. The volatiles increased by pile-fermentation was weakened by aging process. The retained volatiles of pile-fermentation in aging was the basic for aged fragrance. Basic volatiles combined with new volatiles produced in aging formed aged fragrance. Three new volatiles produced in aging were the indicative volatiles of aged fragrance. Abstract: Although aged fragrance is the most outstanding quality characteristic of dark tea, its formation still is not much clear. Thus, the volatiles of Qingzhuan tea (QZT) during the whole post-fermentation process were investigated at an industrial scale. The results showed that most of volatiles increased during pile-fermentation of QZT and weakened during aging storage, but some new volatiles were produced through aging storage. Hexanal, (E)-2-hexenal, (E)-2-decenal, 2, 6, 6-trimethyl-1-cyclohexene-1-carboxaldehyde, heptanal, (E)-2-octenal, (R)-5, 6, 7, 7a-tetrahydro-4, 4, 7a-trimethyl-2(4H)-benzofuranone, ionone, 2-heptanone, 3-ethyl-4-methyl-1H-pyrrole-2, 5-dione, (R, S)-5-ethyl-6-methyl-3-hepten-2-one, cis -5-ethenyltetrahydro-5-trimethyl-2-furanmethanol, and linalool generated by pile-fermentation should be the basic volatiles of aged fragrance in QZT, and 4-(2, 4, 4-trimethyl-cyclohexa-1, 5-dienyl)-but-3-en-2-one, 6-methyl-5-heptene-2-one, safranal, guaiene, trans -2-(2-propynyloxy)-cyclohexanol, nonanal, and 4-(2, 6, 6-trimethyl-1-cyclohexen-1-yl)-2-butanone formed during aging storage should be the transformed volatiles of aged fragrance in QZT, which together constitute the characteristic components of aged fragrance. Notably, 4-(2, 6, 6-trimethyl-1-cyclohexen-1-yl)-2-butanone, 6-methyl-5-heptene-2-one, and safranal were selected as the key volatiles of QZT. These results contribute to understand better the formation of aged fragrance in dark tea.