JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
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2024
·
IF 3.3
Lu Wang,Mingchun Wen,Yu Zhou,Liang Zhang
BACKGROUND Roasting is an essential step in making roasted teas, and its role in producing flavors has been widely studied. However, the variation of potential hazardous compounds during the tea roasting process is still vague. The present study established an effective method based on liquid chromatography-triple quadrupole-tandem mass spectrometry to simultaneously determine the variation of acrylamide (AA), 5-hydroxymethylfurfural (5-HMF), and free amino acids during the tea roasting process. Meanwhile, the effects of several tea polyphenols on the formation of AA and 5-HMF were investigated by a wet-to-dry thermal model reaction. RESULTS Medium-temperature roasted teas had the highest levels of AA and 5-HMF, with ranges of 0.13–0.15 μg g −1 and 68.72–123.98 μg g −1 , respectively. Quantitative results showed that the levels of monosaccharides and amino acids decreased during roasting, which might contribute to the formation of 5-HMF and AA. Meanwhile, the decrease of epigallocatechin gallate (EGCG), epigallocatechin (EGC), and epicatechin (EC) might be related to their inhibitory effects on 5-HMF and AA. Thermal model reaction results showed that EGCG and EC significantly inhibited 5-HMF formation with a decline rate of 33.33% and 72.22%, respectively, mainly by trapping glucose. Gallic acid (GA) also had an inhibitory effect on the formation of AA (decreased by 92.86%) and 5-HMF (44.44%), mainly through impeding the preliminary reaction of asparagine and glucose. CONCLUSION The roasting temperature determined the levels of AA and 5-HMF in teas. Catechins inhibited the formation of 5-HMF and AA mostly through trapping monosaccharides, while the inhibitory effect of GA was achieved by impeding the reaction. © 2024 Society of Chemical Industry.
研究领域:
食品科学
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分析化学
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植物化学
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DOI
PubMed
高影响因子
Plants-Basel
·
2025
·Vol. 15
·期 1
·23
·
IF 4.1
Yuting Li,Shuaibo Shao,Siwei Deng,Zhendong Zhang,Yu Pan,Xingyuan Yao,Chengzhe Zhou,Zhong Wang,Yuqiong Guo
Oolong tea presents notable variations in taste profile and aroma characteristics under different cultivation conditions, particularly across altitudes. However, systematic investigations into the altitude-induced differences in key taste compounds and aroma composition remain limited. In this study, we examined six oolong tea cultivars, comparing their taste-related chemical constituents and aroma profiles under high- and low-altitude cultivation. Sensory evaluation, high-performance liquid chromatography (HPLC) and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were employed to characterize these differences. Sensory evaluation revealed that high-altitude oolong teas exhibited enhanced umami, sweetness, and floral intensity. In most cultivars, the levels of free amino acids, polyphenols, and soluble sugar were relatively higher under high-altitude conditions. HS-SPME-GC-MS identified 55 common volatile organic compounds (VOCs), with terpenes and esters comprising the largest number of compounds. Identification by partial least squares discriminant analysis (PLS-DA) combined with relative odor activity value (rOAV) screening yielded 22 candidate differential volatile organic compounds. Floral monoterpenes, including linalool, linalool oxide II and geraniol, were consistently higher in high-altitude teas, whereas most other volatiles varied primarily with cultivar rather than altitude. These chemical patterns are consistent with the sensory finding of stronger floral intensity in high-altitude samples. This study provides theoretical insights for cultivar selection and quality improvement of oolong tea grown in high-altitude regions.
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PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Wenkai Zhang,Wei Chen,Hongjing Pan,Alireza Sanaeifar,Yan Hu,Wanghong Shi,Jie Guo,Lejia Ding,Jihong Zhou,Xiaoli Li,Yong He
Identifying the aging time of Liu-Pao Tea (LPT) presents a persistent challenge. We utilized an AI-Multimodal fusion method combining FTIR, E -nose, and E-tongue to discern LPT's aging years. Compared to single-source and two-source fusion methods, the three-source fusion significantly enhanced identifying accuracy across all four machine learning algorithms (Decision tree, Random forest, K-nearest neighbor, and Partial least squares Discriminant Analysis), achieving optimal accuracy of 98–100 %. Physicochemical analysis revealed monotonic variations in tea polysaccharide (TPS) conjugates with aging, observed through SEM imaging as a transition from lamellar to granular TPS conjugate structures. These quality changes were reflected in FTIR spectral characteristics. Two-dimensional correlation spectroscopy (2D-COS) identified sensitive wavelength regions of FTIR from LPT and TPS conjugates, indicating a high similarity in spectral changes between TPS conjugates and LPT with aging years, highlighting the significant role of TPS conjugates variation in LPT quality. Additionally, we established an index for evaluating quality of aging, which is sum of three fingerprint peaks (1029 cm −1 , 1635 cm −1 , 2920 cm −1 ) intensities. The index could effectively signify the changes in aging years on macro-scale (R 2 = 0.94) and micro-scale (R 2 = 0.88). These findings demonstrate FTIR's effectiveness in identifying aging time, providing robust evidence for quality assessment.
研究领域:
食品科学
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化学计量学
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光谱学
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人工智能
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分析化学
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产品关联
DOI
PubMed
高影响因子
Journal of Future Foods
·
2026
·
IF 10.6
Jinjie Hua,Liyue Yang,Jianqiang Ma,Xiwang Li,Ting An,Fenglan Zhang,Ming Chen,Xinxin Lv,Jiayi Zhu,Jinjin Wang,Haibo Yuan,Yongwen Jiang
Tea varieties are key factors influencing tea type and flavor quality. However, the key biochemical indicators biochemical indicators associated with tea varietal suitability remain unclear, and the traditional phenol-ammonia ratio is insufficient as an evaluation criterion. Therefore, identifying reliable biochemical markers for evaluating tea varietal suitability is important for optimizing tea processing and product quality. We aimed to identify key biochemical indicators associated with tea varietal suitability for black and green tea processing and to establish a predictive model for evaluating tea varietal adaptability. Molecular biology and targeted metabolomics approaches were used to analyze polyphenol oxidase (PPO) activity, the expression of three PPO isozymes, and the contents of 60 non-volatile metabolites (NVMs) in fresh leaves from 20 representative tea varieties. Variable importance in projection, S-plot, taste active value, and classification analyses were applied to identify key differential indicators. A predictive model for tea varietal suitability was subsequently developed using data preprocessing and regression analysis. Nine key differential biochemical indicators, including epigallocatechin gallate, epicatechin gallate, epigallocatechin, epicatechin, catechin, myricetin-3-O-galactoside, theaflavin-3-3′-di-O-gallate, theanine, and glutamic acid, together with three enzyme-related indicators, namely PPO activity and the expression levels of PPO2 and PPO4, were identified. Tea varieties suitable for black tea exhibited high levels of epigallocatechin gallate, epicatechin gallate, theaflavin-3-3′-di-O-gallate, and PPO activity, particularly PPO4 expression. In contrast, tea varieties suitable for green tea showed high levels of epigallocatechin, epicatechin, theanine, glutamic acid, and myricetin-3-O-galactoside content. A 1DER+MINMAX data preprocessing method and predictive model effectively evaluated tea varietal suitability. This study identified key biochemical indicators associated with tea varietal suitability and established a predictive model for evaluating tea adaptability for black and green tea processing. These findings provide theoretical and technical support for the efficient utilization of fresh leaf leaves and tea product development.
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高影响因子
FOOD CONTROL
·
2021
·
IF 5.548
Dandan Qi,Aiqing Miao,Wei Chen,Wenwen Wang,Xiugu He,Chengying Ma
Broken oolong-black tea is an innovative tea in China produced by applying characteristic manufacture crafts of broken oolong tea (bruising) and broken black tea (fermentation) on the manufacture of tea and it has both aroma features of broken oolong tea and broken black tea. The aim of this study is to investigate the differences of the volatile compounds among broken oolong-black, broken oolong and broken black tea made by Huangzhixiang (HZX) and Huangdan (HD) varieties by gas chromatography-mass spectrometry (GC-MS) combined with chemometirc analysis. The results suggested significant differences on both aroma quality and volatile compounds profile of three kinds of tea. Chemometric analysis showed that 47 and 52 differential volatile compounds were identified to distinguish three kinds of teas made by HZX and HD, respectively, and the differences of volatile compounds among the tea samples were mostly quantitatively rather than qualitatively. Besides, compounds with floral and fruity aroma increased in broken oolong-black tea compared with the others, while compounds with green aroma decreased in broken oolong-black tea. Quantitative descriptive analysis of the aroma showed that sweet aroma was a new trait of broken oolong-black tea compared with broken oolong tea while green aroma disappeared compared with broken black tea. Our results provide the theoretical and practical meaning for the application of two characteristic crafts from different tea manufacture on the innovation of tea manufacture.
研究领域:
食品科学
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茶学
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DOI
高影响因子
Food Quality and Safety
·
2020
·Vol. 4
·期 4
·193-201
·
IF 0
Liu Bei,Xu Qingqing,Sun Yujing
Goji berry tea, a traditional herbal tea, is the main ate mode of goji berry in Asia, yet few studies in comparison with red goji berry tea and black goji berry tea are carried out. This study investigated the effects of water temperature and soak time on the colour, phytochemicals, and the antioxidant capacity [2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), and the ferric-reducing antioxidant power (FRAP)] of two goji berry tea. A comparison of the bioactive compounds and antioxidant activities between black and red goji berry tea was conducted. Results showed that both red and black goji berry tea were rich in phytochemicals, giving high antioxidant ability. The levels of bioactive compounds and the antioxidant activity of the two goji berry tea increased as the increases in soak temperature and time. Black goji berry tea had higher phytochemicals and antioxidant property than those of red goji berry tea. Infused at 100° water for the same time, the levels of total polysaccharides (150 mg/100 ml), total polyphenols (238 mg/ml), and antioxidant capacity (550 μmol/100 ml) of black goji berry tea were 3.5, 2, and 5 times higher, respectively, in comparison with red goji berry tea. The results of this study demonstrate that hot drink of goji berry in China is a good habit and black goji berry tea may be a better choice.
研究领域:
食品科学
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植物化学
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营养学
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产品关联
DOI
FOOD RESEARCH INTERNATIONAL
·
2024
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IF 7
Xuyang Liu,Feng Zhou,Mingchun Wen,Shan Jiang,Piaopiao Long,Jia-Ping Ke,Zisheng Han,Mengting Zhu,Yu Zhou,Liang Zhang
To explore the influence of tea trichomes on the quality of white tea, liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS), and headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC–MS) were used to identify non-volatile and volatile compounds white tea without trichomes (WTwt) and pure trichomes (PT). It was found that the bitter and astringent compounds, caffeine (CAF), epigallocatechin gallate (EGCG), epicatechin gallate (ECG) and flavonol glycosides, were mainly enriched in the WTwt, with 16.3-fold, 47.1-fold and 28.7-fold decrease in CAF and EGCG and ECG, respectively, and the content of these compounds in PT were lower than the taste thresholds. In PT, kaempferol-3- O -( p -coumaroyl)-glucoside and kaempferol-3- O -(di- p -coumaroyl)-glucoside were non-volatile marker compounds, and decanal was significant aroma contributor with rOAV = 250.86. Moreover, the compounds in trichomes mainly contributed to the fruity and floral aroma of white tea, among which benzyl alcohol, (E) -geranylacetone, decanal, dodecanal and 6-methyl-5-hepten-2-one were the crucial aroma components, which were 2.1, 1.7, 1.8, 1.4 and 2.2 times as much as the WTwt in the PT, respectively. In conclusion, trichomes can improve the quality of white tea by reducing the bitterness and astringency, increasing the umami, as well as enhancing the fruity and floral aromas.
研究领域:
植物学
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化学
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食品科学
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代谢组学
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DOI
PubMed
高影响因子
Food Chemistry-X
·
2025
·
IF 8.2
Jing Wang,Yuemeng Hu,Zhenyu Guan,Ronggang Zhai,Jieyao Yu,Marina Rigling,Yanyan Zhang,Xiaochun Wan,Xiaoting Zhai
Large-leaf yellow tea (LYT) is a yellow tea product with a specific aroma characteristic and the flavor code has recently been revealed. To elucidate the transformation of odorants from fresh leaves to finished LYT, this study tracked dynamic changes in aroma compounds throughout an industrial-scale experiment. The odorants' contributions of each step were evaluated by stable isotope dilution assays, internal standard method, and odor activity values. Among 39 quantitated odorants, the loss of top-note compounds such as dimethyl sulfide, 2-/3-methylbutanal, and 2-methylpropanal during yellowing was compensated during roasting. In contrast, floral compounds like geraniol and linalool declined progressively, while pyrazines were mainly generated during the final roasting and increased with roasting intensity. Therefore, yellowing and roasting steps were identified as key processes influencing LYT aroma formation, and the roasting degree significantly influenced the final aroma profile. These findings provide a mechanistic understanding of aroma development in LYT and offer practical guidance for optimizing processing parameters to tailor flavor profiles.
研究领域:
食品科学
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茶叶化学
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DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2025
·
IF 8
Shiqiang Peng,Lianzhu Lin,Mouming Zhao
Drinking tea is beneficial to reduce the incidence of obesity. Unlike Fuzhuan brick tea (DT, a typical dark tea) widely reported to have good glycolipid-lowering activity (GLA), there is little information on GLA of Dancong summer tea (OT, a typical oolong tea). A comparative study on GLA and chemical compositions of OT and DT was systematically conducted. The results showed that OT had advantages in high content of polyphenols, leading to its better GLA including glycolipid digestion enzyme inhibitory activity and cholesterol micellar solubility inhibition activity than DT’s. A total of 21 compounds mainly including catechins, flavonoids, phenolic acids and phenylpropanoids were screened as the key differentially active micromolecules (KDAM) by UPLC-QTOF-MS/MS-based untargeted metabolomic analysis combined with multivariate analysis, which resulted in the difference of GLA between OT and DT. Moreover, the high affinity capacity and interaction mode between KDAM with α -glucosidase/ α -amylase/pancreatic lipase/cholesterol esterase were validated by molecular docking. Although the accumulation of polyphenols makes OT has a poor flavor as a beverage, our research demonstrated that OT with high content of polyphenols could be used in functional foods to facilitate the prevention of obesity.
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
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2023
·Vol. 24
·期 5
·4640
·
IF 5.6
Anqi Peng,Keke Yu,Shuwei Yu,Yingying Li,Hao Zuo,Ping Li,Juan Li,Jianan Huang,Zhonghua Liu,Jian Zhao
Tea plants have adapted to grow in tropical acidic soils containing high concentrations of aluminum (Al) and fluoride (F) (as Al/F hyperaccumulators) and use secret organic acids (OAs) to acidify the rhizosphere for acquiring phosphorous and element nutrients. The self-enhanced rhizosphere acidification under Al/F stress and acid rain also render tea plants prone to accumulate more heavy metals and F, which raises significant food safety and health concerns. However, the mechanism behind this is not fully understood. Here, we report that tea plants responded to Al and F stresses by synthesizing and secreting OAs and altering profiles of amino acids, catechins, and caffeine in their roots. These organic compounds could form tea-plant mechanisms to tolerate lower pH and higher Al and F concentrations. Furthermore, high concentrations of Al and F stresses negatively affected the accumulation of tea secondary metabolites in young leaves, and thereby tea nutrient value. The young leaves of tea seedlings under Al and F stresses also tended to increase Al and F accumulation in young leaves but lower essential tea secondary metabolites, which challenged tea quality and safety. Comparisons of transcriptome data combined with metabolite profiling revealed that the corresponding metabolic gene expression supported and explained the metabolism changes in tea roots and young leaves via stresses from high concentrations of Al and F. The study provides new insight into Al- and F-stressed tea plants with regard to responsive metabolism changes and tolerance strategy establishment in tea plants and the impacts of Al/F stresses on metabolite compositions in young leaves used for making teas, which could influence tea nutritional value and food safety.Keywords:aluminum and fluoride;organic acid;secondary metabolite;tea quality;tea safety
研究领域:
植物生理学
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代谢组学
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食品安全
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农学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Xin Fang,Wencan Xu,Guangxian Jiang,Mengyuan Sui,Jingyi Xiao,Yaoyao Ning,Rida Niaz,Dewen Wu,Xiaoguang Feng,Junhai Chen,Youyi Huang,Gaixiang Lei
Aroma is one of the most outstanding quality characteristics of Qingzhuan tea (QZT), but its formation is still unclear. Thus, the volatile organic compounds (VOCs) during the whole processing of QZT were investigated by headspace solid-phase microextraction/gas chromatography-mass spectrometry. Based on 144 identified VOCs, the results showed that de-enzyming, sun-drying, and piling fermentation were the key processes of QZT aroma formation. Furtherly, 42 differential VOCs (VIP > 1.0 and p < 0.05) and 16 key VOCs (rOAV > 1.0 and/or ROAV > 1.0) were screened. Especially, sulcatone and β -ionone (rOAV > 100 and ROAV > 10) were considered the most important contributors to the aroma of QZT. The metabolisms of key VOCs were mainly involved in oxidative degradation of fatty acids, degradation of carotenoids, and methylation of gallic acid. This study could help to more comprehensively understand the aroma formation in QZT processing at an industrial scale.
研究领域:
食品科学
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植物学
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代谢组学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF FOOD PROPERTIES
·
2025
·
IF 3.9
Zhen Liu,Peidi Yang,Yang Zhao,Furong Qu,Yang Cheng
We performed volatile and nonvolatile metabolome analysis of Zhuyeqi (Z) and Baihaozao (B) dark teas during three stages of tea processing: (1) after withering and kneading (S), (2) after pile-fermenting (M), and (3) during drying and second kneading (Z). Our results indicate that the Z variety was rich in glycerophospholipids, isoflavonoids, morphinans, organic oxides, organic phosphonic acids, purines, and thiadiazines. A total of 427 metabolites were differentially accumulated between Z and B during three stages of processing (S, M, and Z). These metabolites were significantly enriched in ABC transporters, flavonoid biosynthesis, tyrosine metabolism, glutamic acid, linoleic acid metabolism, etc. Epicatechin, phenylacetic acid, (-)-cis-carveol, and neochlorogenic acid had higher levels in Z. Forty-three volatile compounds were differentially accumulated in BvsZ and their accumulation levels were affected by processing. The variety Z had a higher relative percentage of alcohols, and esters. Forty-six of the 75 substances contributed to the tea aroma. ZT had compounds with higher ROAV values such as furan (caramel-like and sweet fruity), 2-pentyl- (green beans, vegetable), heptanal (citrus, fatty, and rancid), and others. In total, 113 unique flavors were associated with substances that accumulated at higher levels in ZT. Our results suggest that Z offers a better composition and flavor profile than B due to the higher quantities of several health beneficial and taste-related compounds at the same processing stages.
研究领域:
代谢组学
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食品科学
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植物生物化学
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农业科学
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分析化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）