Horticultural Plant Journal
·
2024
·
IF 5.7
Sanyan Lai,Ning Yi,Shixin Yin,Yipeng Huang,Tianlin Shen,Qianying Dai,Liping Gao,Xiaolan Jiang,Tao Xia
Tea flavor is a comprehensive representation of its aroma and other characteristics. The formation of volatile odor compounds during tea processing depends on a variety of enzymatic and non-enzymatic activities. ( Z )-3-hexenol is considered the primary source of the green odor and is also the most important component in tea aroma, significantly affecting the overall aroma. However, the biosynthesis and accumulation of ( Z )-3-hexenol during tea processing have not been fully analyzed. In this study, we found that withering treatment at different times and withering plus shaking treatment at different degrees promoted the accumulation of important volatile components of green tea odor, especially ( Z )-3-hexenol by GC-MS. The RNA-seq and qRT-PCR results showed that withering and withering plus shaking treatments enhanced the expression of ( Z )-3-hexenol-related genes in tea leaves, including synthetic pathway 1 genes ( CsLOX3 , CsHPL1 , CsADH4 , and CsAHD1 ), synthetic pathway 2 genes ( CsGLU ), and synthetic pathway 3 genes ( CsCXEs ). Correlation analysis of the key odorants and important genes in the three synthetic pathways revealed that some CsCXEs were positively correlated with green odor compounds. The in vitro enzyme activity results showed that rCsCXE3 (GWHTASIV011658), and rCsCXE6 (GWHTASIV031480) exhibited hydrolytic activity against three tea acetate compounds [hexyl acetate, ( E )-2-hexyl acetate, and ( Z )-3-hexyl acetate], resulting in the production of corresponding alcohol compounds. In summary, withering and shaking treatment during tea processing promoted the expression of CsCXE3 and CsCXE6 , thereby enhancing the production of hexenol compounds. These compounds play a crucial role in increasing the green odor of tea.
研究领域:
植物学
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分子生物学
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产品关联
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2024
·
IF 7
Qiwei Wang,Jialing Xie,Lilei Wang,Yongwen Jiang,Yuliang Deng,Jiayi Zhu,Haibo Yuan,Yanqin Yang
Processing technology plays a crucial role in the formation of tea aroma. The dynamic variations in volatile metabolites across different processing stages of fresh scent green tea (FSGT) were meticulously tracked utilizing advanced analytical techniques such as GC-E-Nose, GC–MS, and GC × GC-TOFMS. A total of 244 volatile metabolites were identified by GC–MS and GC × GC-TOFMS, among which 37 volatile compounds were concurrently detected by both methods. Spreading and fixation stages were deemed as pivotal processes for shaping the volatile profiles in FSGT. Notably, linalool, heptanal, 2-pentylfuran, nonanal, β -myrcene, hexanal, 2-heptanone, pentanal, 1-octen-3-ol, and 1-octanol were highlighted as primary contributors to the aroma profiles of FSGT by combining odor activity value assessment. Furthermore, lipid degradation and glycoside hydrolysis were the main pathways for aroma formation of FSGT. The results not only elucidate the intricate variations in volatile metabolites but also offer valuable insights into enhancing the processing techniques for improved aroma quality of green tea.
研究领域:
食品科学
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植物学
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分析化学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Jue Liu,Youjun Hu,Jie Zheng,Pan Yue,Shi-Yi Ou,Jiaqi Lu,Xiting Huang,Wanyi Cao,Hua Zhou
Methylselenocysteine (SeMC), the primary organic selenium in tea, enhances human nutrition through its bioavailability and bioactivity (e.g. antioxidant activity). This study investigated SeMC stability during tea processing: high-temperature fixation caused 48.11 % SeMC loss (vs. 25.54 % when rolling at 25 °C), following first-order kinetics ( Ea = 65.58 kJ/mol, air). Nitrogen protection reduced degradation to <10 % at 150 °C. We first report that 29.19 % of oxidised SeMC (SeMCO) regenerates to SeMC at 25 °C, challenging the assumed irreversibility of selenium oxidation. Catalase (≥200 U/mg) synergized with nitrogen to inhibit oxidation, enabling 1) shortened thermal exposure, 2) nitrogen blanketing, and 3) enzymatic control. These results provide practical solutions to preserve selenium functionality during tea processing, thus advancing selenium-rich food production.
研究领域:
食品科学
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营养学
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植物化学
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产品关联
DOI
PubMed
高影响因子
Current Research in Food Science
·
2024
·
IF 6.2
Shan Zhang,Le Chen,Linchi Niu,Haibo Yuan,Xujiang Shan,Qianting Zhang,Yuning Feng,Qinghua Zhou,Yongwen Jiang,Jia Li
Lipids are important tea aroma precursors. Due to the complexity of black tea processing involving both enzymatic and thermal reactions, the role of lipids in black tea aroma formation remained unclear. Herein, the dynamic changes of lipids and volatiles during black tea processing were simultaneously analyzed by lipidomics and volatolomics using ultra-high-performance liquid chromatography coupled to Q-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive) and gas chromatography-tandem mass spectrometry (GC-MS/MS). The lipidomics method was validated in linearity, reproducibility, and recovery, which showed a high reliability. A total of 374 lipids and 88 volatiles were detected. Among them, 362 lipids and 29 fatty acid-derived volatiles (FADVs) were significantly altered depending on different processing stages. During the enzyme-driven stages of black tea processing (withering, rolling and fermentation), monogalactosyldiacylglycerol (MGDG), phosphatidylcholine (PC), and phosphatidylethanolamine (PE) were largely downregulated (<0.33 folds). Instead, in the non-enzymatic drying steps of black tea processing, triacylglycerol (TG), diacylglycerol (DG), and phosphatidic acid (PA) were mainly degraded (<0.24 folds). MS/MS fragmentation revealed that these most prominently degraded lipids were structurally enriched with fatty acyl (FA) 18:2 and 18:3 residues, such as MGDG (18:2/18:3), PC (18:2/18:2), PE (18:1/18:2), TG (18:3/18:3/18:3), DG (18:3/18:3), PA (18:3/18:3). Correlation analysis showed significant negative correlation between these lipids and FADVs such as aliphatic aldehydes, alcohols, ketones, and esters, etc. These most prominently degraded lipids were highlighted as the key potential aroma precursors during black tea processing, which were possibly oxidized and degraded into volatiles through enzyme- and thermal-driven pathways at different processing stages.
研究领域:
食品科学
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植物代谢组学
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茶叶研究
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Jialing Xie,Lilei Wang,Yuliang Deng,Haibo Yuan,Jiayi Zhu,Yongwen Jiang,Yanqin Yang
To characterize the key odorants of floral aroma green tea (FAGT) and reveal its dynamic evolution during processing, the volatile metabolites in FAGT during the whole processing were analyzed by integrated volatolomics techniques, relative odor activity value (rOAV), aroma recombination, and multivariate statistical analysis. The volatile profiles undergone significant changes during processing, especially in the withering and fixation stages. A total of 184 volatile compounds were identified (∼53.26% by GC-MS). Among them, 7 volatiles with rOAV > 1 were identified as characteristic odorants of FAGT, and most of these compounds reached the highest in withering stage. According to the formation pathways, these key odorants could be divided into four categories: fatty acid-derived volatiles, glycoside-derived volatiles, amino acid-derived volatiles, and carotenoid-derived volatiles. Our study provides a comprehensive strategy to elucidate changes in volatile profiles during processing and lays a theoretical foundation for the targeted processing of high-quality green tea.
研究领域:
食品科学
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茶叶研究
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植物代谢组学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
·
2024
·
IF 3.3
Yunzhi Lin,Qing Meng,Yiwen Miao,Linmu Chen,Cuixin Huang,Jirui Kun,Zhengfei Luo,Huarong Tong
BACKGROUND Broken black tea (BBT) is the most consumed black tea in the world. Laurie tea processor black tea (LTP-BT) is one of the most important categories of BBT. In this study, the fresh leaves of three tea plant cultivars including Golden Peony tea, Yunnandaye, and Fuding Dabai were blended to process LTP-BT using the simplex centroid design. Using gas chromatography–mass spectrometry and high-performance liquid chromatography, the differences in volatile and non-volatile components of LTP-BT under different formulations were analyzed. RESULTS A total of 88 volatile compounds were detected, among which 16 aroma compounds, including benzyl alcohol, linalool, and methyl salicylate, could be identified as key common aroma substances in BBT. Following evaluation of the model, Golden Peony 16.7%, Fuding Dabai 16.7%, and Yunnan Daye 67.8% were the best proportions in mixed fermentation of LTP-BT. The LTP-BT produced in this ratio had a high and lasting aroma, strong and mellow taste, and bright and red soup color. CONCLUSION Our study showed that mixed fermentation is feasible for the manufacturing process of LTP-BT, and the simplex centroid design would be a reliable guide for cultivar formulation, providing customers with an alterable flavor and consumption feature. © 2024 Society of Chemical Industry.
研究领域:
食品科学
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植物学
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化学
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产品关联
DOI
PubMed
高影响因子
Food Chemistry: Molecular Sciences
·
2023
·
IF 3.3
Ying Zhou,Wei He,Yunchuan He,Qiulin Chen,Yang Gao,Jiamei Geng,Zeng-Rong Zhu
Linalool and its derivatives contribute greatly to tea aroma. Here, 8-hydroxylinalool was found to be one of the major linalool-derived aroma compounds in Camellia sinensis var. assamica ‘Hainan dayezhong’, a tea plant grown in Hainan Province, China. Both ( Z )-8-hydroxylinalool and ( E )-8-hydroxylinalool were detected, and the E type was the main compound. Its content fluctuated in different months and was the highest in the buds compared with other tissues. CsCYP76B1 and CsCYP76T1, located in the endoplasmic reticulum, were identified to catalyze the formation of 8-hydroxylinalool from linalool in the tea plant. During withering of black tea manufacturing, the content of both ( Z )-8-hydroxylinalool and ( E )-8-hydroxylinalool significantly increased. Further study suggested that jasmonate induced gene expression of CsCYP76B1 and CsCYP76T1 , and the accumulated precursor linalool may also contribute to 8-hydroxylinalool accumulation. Thus, this study not only reveals 8-hydroxylinalool biosynthesis in tea plants but also sheds light on aroma formation in black tea.
研究领域:
植物生物化学
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茶学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2021
·
IF 5.279
Jing Zhang,Huiyan Jia,Biying Zhu,Junyao Li,Tianyuan Yang,Zheng-Zhu Zhang,Wei-Wei Deng
Methyl jasmonate (MeJA), a volatile organic compound, is a principal flowery aromatic compound in tea. During the processing of black tea, MeJA is produced by jasmonic acid carboxyl methyltransferase (JMT) of the jasmonic acid (JA) substrate, forming a specific floral fragrance. CsJMT was cloned from tea leaves; the three-dimensional structure of CsJMT was predicted. Enzyme activity was identified, and protein purification was investigated. Site-directed deletions revealed that N-10, S-22, and Q-25 residues in the beginning amino acids played a key functional role in enzyme activity. The expression patterns of CsJMT in tea organs differed; the highest expression of CsJMT was observed in the fermentation process of black tea. These results aid in further understanding the synthesis of MeJA during black tea processing, which is crucial for improving black tea quality using specific fragrances and could be applied to the aromatic compound regulation and tea breeding improvement in further studies.
研究领域:
植物生物化学
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分子生物学
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食品科学
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茶叶科学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Jie-Qiong Wang,Yan-Qing Fu,Jian-Xin Chen,Fang Wang,Zhi-Hui Feng,Jun-Feng Yin,Liang Zeng,Yong-Quan Xu
Seven batches of raw tea leaves, processed by different methods (steaming, pan-frying) and from two different harvesting seasons (spring, autumn), were used to investigate the effect of baking treatment on changes in the composition and content of nonvolatile and volatile compounds. The results showed that baking had a greater impact on sensory and flavor quality, which chemically modified some of taste and aroma components. The aroma concentrations of steamed teas (4,168–10,706 μg/L) were significantly higher than those of pan-fried teas (959–2,608 μg/L), and the aroma concentrations of baked green teas (2,608–10,706 μg/L) were significantly higher than those of unbaked teas (959–4,213 μg/L). Based on VIP > 1 and ACI > 1, (E, E)-3,5-octadien-2-one, hexanal, β-ionone, 5-methylfurfural, β-cyclocitral, and linalool were identified as the main aroma compounds. Chemical changes resulting from Maillard reaction were greater during baking of steamed, than pan-fried green tea. These results help improve the quality of green tea with baking.
研究领域:
食品科学
·
茶叶化学
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DOI
PubMed
高影响因子
Foods
·
2025
·Vol. 14
·期 18
·3159
·
IF 5.1
Changlian Wu,Huang Li,Qingxiu Lin,Zhong Wang,Chengzhe Zhou,Cheng Zhang,Yuqiong Guo
One of the main factors constraining the growth of the tea business is the low use rate of summer tea. To enhance the utilization rate and improve the quality of summer tea, this study innovatively integrated shaking, freezing, and rolling into the traditional processing methods of white tea. Processing parameters were optimized through single-factor experiments combined with an L9(34) orthogonal experimental design. The quality of summer teas was systematically evaluated using sensory analysis, gas chromatography–mass spectrometry, and high-performance liquid chromatography. This study found that the optimal processing for summer tea was as follows: fresh leaves, room-temperature cold-air withering for 6.5 h, shaking at 10 rpm for 10 min, −20 °C freezing for 5 h, 25% strength rolling for 9 min, and drying at 75 °C for 2 h. The relative content of esterified catechins in summer tea produced by the optimal processing method was reduced by 14.62% compared with the control group. There were alterations in the content of amino acid components, with fresh and sweet amino acids increasing by 4.96% and 2.95%, respectively, and bitter amino acids reducing by 2.15%. Furthermore, γ-aminobutyric acid and L-theanine contents increased by 0.51% and 5.77%, respectively. Five characteristic volatile compounds were identified, namely, methyl salicylate, phenethyl formate, linalool, dimethyl sulfide, and isobutyraldehyde. The volatile profile was dominated by floral and fruity notes, except for dimethyl sulfide, which exhibited a distinct cooked corn-like aroma characteristic. This process was shown to improve the quality of summer tea. The results of this study provide a metabolite-level grounds for improving the quality of summer tea.
研究领域:
食品科学与技术
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茶叶加工工程
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植物生物化学
·
代谢组学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）