Food Chemistry-X
·
2024
·
IF 6.5
Zixin Ni,Wei Chen,Hongjing Pan,Dengchao Xie,Yuefei Wang,Jihong Zhou
Tea foam properties, crucial indicators of tea quality, have gained renewed interest due to their potential applications in innovative beverages and foods. This study investigated the foaming properties and chemical foundations of six major tea categories through morphological observations and biochemical analyses. White tea exhibited the highest foaming ability at 56.28%, while black tea showed the best foam stability at 84.01%. Conversely, green tea had the lowest foaming ability (10.83%) and foam stability (54.24%). These superior foaming characteristics are attributed to the relatively low lipid content and acidic pH values. Surprisingly, no significant correlation was found between tea saponin content and foaming properties. Instead, specific amino acids (including Tyr, Gaba, Phe, Ile, and Leu) and catechins (GA and CG) were identified as potential contributors. These results deepen our understanding of tea foam formation and offer insights into utilizing tea-derived plant-based foams in food products.
研究领域:
食品科学
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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 FOOD SCIENCE AND TECHNOLOGY
·
2018
·Vol. 54
·期 2
·490-498
·
IF 2.383
Zhou-Tao Fang,Chu-Jun Song,Hai-Rong Xu,Jian-Hui Ye
Summary Flavonol glycosides with low thresholds are important flavour substances in tea leaves. This study monitored the dynamic changes in flavonol glycosides during the production of different teas. The fresh leaves of cv. Fudingdabaicha with 15.77 mg g −1 of total flavonol glycosides (TFG) were respectively processed into green, yellow, white, oolong and black teas. A reduction of TFG was observed for different teas, amongst which black tea contained the lowest level of TFG (9.83 mg g −1 ), followed by oolong tea (11.96 mg g −1 ), while green, yellow and white teas contained similar levels of TFG (~13.70 mg g −1 ). Fixation was crucial to maintain the stability of flavonol glycosides due to its inactivation effect on enzymes at high temperature. Principal component analysis results indicated that flavonol glycosides were vulnerable to fermentation, and the stabilities of flavonol glycosides were related with aglycone and glycoside moiety.
研究领域:
植物化学
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食品科学
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茶叶加工学
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产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2018
·
IF 3.129
Lujing Xu,Guobin Xia,Zisheng Luo,Songbai Liu
In this study, an effective ultra-high performance liquid chromatography (UHPLC) method for simultaneous determination of 15 constituents of catechins, caffeine, gallic acid and theaflavins was developed. Employing the developed UHPLC method, the contents of the 15 constituents were analyzed in 245 samples of 6 types of Chinese teas collected from different places. The catechin contents in these samples ranged from 16.50 to 94.35 mg/g. Theaflavins were not detected in green tea and white tea, and caffeine did not strongly relate to germplasm resource or fermentation degree. Principal component analysis (PCA) of UHPLC data revealed that white, oolong and green tea samples could be clustered closely, demonstrating notable difference of functional components between the three types of teas resulting from preparation process and varieties. The constituent profile could be primarily attributed to the structural transformation of catechins and pigments during tea processing. This study would advance our understanding of chemical profile of Chinese teas afforded by different processing technologies.
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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产品关联
DOI
高影响因子
Food Chemistry-X
·
2024
·
IF 6.5
Ji Wang,Jing Che,Xu-Song Wang,Lei Qin,Xu-Hui Huang
The levels of flavor compounds and hazardous compounds are important indicators for evaluating high-temperature roasted food. In this paper, the effect of tea pre-marination on non-volatile compounds, volatile compounds, and hazardous compounds in roasted chicken. The results showed that the total content of key umami non-volatile compounds in roasted chicken marinated with green tea, white tea, and black tea increased by 17.43 % to 100.11 %. The content of alkenes, alcohols, aldehydes, and ketones in high-temperature roasted chicken marinated with oolong tea and yellow tea was increased. Different teas had varying inhibitory effects on hazardous compounds in high-temperature roasted chicken, while green tea exhibited the highest inhibition efficacy. The inhibition rates of green tea for ACY, 5-HMF, HCAs, and PAHs were 72.12 %, 69.87 %, 92.49 %, and 14.92 %, respectively. Flavonoids in tea may play an important role in the flavor enhancement and hazardous compounds inhibition of high-temperature roasted chicken.
研究领域:
食品科学
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化学
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营养学
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产品关联
DOI
PubMed
高影响因子
PLANT FOODS FOR HUMAN NUTRITION
·
2009
·Vol. 64
·期 4
·293-296
·
IF 1.69
Chen Yulong,Duan Jun,Yang Shaoyu,Yang En,Jiang Yuming
Oolong tea is one of the most popular beverages due to the presence of significant amount of catechins. Experiments were conducted to investigate the effect of girdling treatment on levels of catechins in fresh tea leaf related to quality of the ‘Huang Zhi Xiang’ Oolong tea ( Camellia sinensis ). The variations in the levels of catechins in fresh tea leaf and the quality score (QS) of the ‘Huang Zhi Xiang’ Oolong tea were examined. The study demonstrated that girdling treatment increased significantly the levels of (−)-epicatechin, (−)-epigallocatechin, (−)-epigallocatechin gallate, (−)-epicatechin gallate, total catechins, simple catechin, and catechin gallate present in fresh leaf of tea trees. Furthermore, the girdling treatment improved significantly the quality of the ‘Huang Zhi Xiang’ Oolong tea. Thus, it was suggested that application of girdling treatment could be an effective agronomic practice to increase the quality of ‘Huang Zhi Xiang’ Oolong tea.
研究领域:
园艺学
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植物生理学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2024
·
IF 4
Yujie Ai,Qidi Wu,Haibo Yuan,Yingqin He,Yongwen Jiang,Suzhen Niu
Catechins and theaflavins , as the primary bioactive constituents of black tea, have a significant impact on its color, aroma, and flavor profile. We developed a rapid and precise method using HPLC to detect catechins and theaflavins in black tea. The method employed 0.1% formic acid-acetonitrile (phase A) and 1% formic acid-water (phase B) as mobile phases . Separation occurred on an Agilent SB-C18 column (4.6 mm × 250 mm, 5 µm), with 20 μL injection volume. Detection took place at 30 °C with a flow rate of 1 mL/min for 55 min.Quantitative determination utilized the external standard method, exhibiting high sensitivity (limit of detection: 0.19 to 5.14 μg/mL) and a strong linear correlation (R2 ≥ 0.9993) between concentration range and peak area. Precision, repeatability, and stability were excellent, with relative standard deviations (RSDs) below 5% (n = 5). The average recovery rate of standard addition ranged from 98.02% to 102.57%, with an RSD of less than 3.17% (n = 5). In summary, this straightforward, efficient, and precise approach is well-suited for both qualitative and quantitative analysis of catechins and theaflavins in tea. It overcomes the limitations of previous methods, providing a valuable tool for evaluating the quality and composition of black tea.
研究领域:
食品科学
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分析化学
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产品关联
DOI
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2024
·
IF 4
Xiaoyan Shen,Xiaofen Wu,Hui Qi,Dongning Wei,Ming Deng,Keqin Wang,An Liu,Liang Chen
This study focused on the efficiency of enzymatic synthesis for theaflavins (TFs) and SII types of thearubigins (SII-TRs) in suspended fermentation of different varieties of tea leaves. The results showed that the content of catechins in tea variety-Xiaoxianghong 21-3 (XXH21-3) was the highest among the five kinds of fresh tea leaves, and it had the strongest ability of transforming catechins to TFs and SII-TRs. The total amount of catechins for XXH 21-3 decreased rapidly and the conversion ratio of TFs reached the highest level of 13.96% after 20 min, the residual catechins was the lowest (3.08%) and the conversion rate of SII-TRs was the highest (13.02%) after 120 min during the suspended fermentation of five varieties tea leaves. Among the six catechin types, epicatechin gallate (ECG), epigallocatechin gallate (EGCG) and epigallocatechin (EGC) were consumed in large quantities, and the residues were all less than 5% in the final stage of fermentation, of which ECG consumption was the fastest, followed by EGCG. These results demonstrated that the concentration of catechins and PPO activities were positively correlated with the formation of TFs and SII-TRs, POD activity was positive correlation with synthesis of SII-TRs and negative correlation with TFs.
研究领域:
食品科学
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茶叶化学
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酶学
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产品关联
DOI
高影响因子
PLANT FOODS FOR HUMAN NUTRITION
·
2011
·Vol. 66
·期 2
·169-174
·
IF 2.463
Chen Yulong,Jiang Yueming,Shi John,Xu Xinlan,Yang Shaoyu,Duan Jun
The contents of starch and catechins in the fresh leaf of ‘Huang Zhi Xiang’ Oolong tea trees girdled at the bottom, middle (on the big branches) and top (on the small branches) were determined. The study demonstrated that the starch contents from girdled trees were significantly higher ( p < 0.05) than that from non-girdled ones. Furthermore, the contents of (−)−epicatechin (EC), (−)−epigallocatechin (EGC), total catechins (TC) and simple catechins (SC) from girdled trees were significantly higher ( p < 0.05) than those from non-girdled ones. Especially, the contents of (−)−epigallocatechin gallate (EGCG), (−)−epicatechin gallate (ECG) and catechin gallate (CG) from girdled at the middle were also significantly higher ( p < 0.05) than those from the non-girdled. The starch contents were negatively correlated with the contents of (−)−gallocatechin (GC), EC, SC, TC and EGC, while positively correlated with the contents of EGCG and CG in fresh shoots.
研究领域:
植物学
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茶叶科学
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DOI
PubMed
高影响因子
Food Chemistry-X
·
2024
·
IF 6.5
Wenjing Huang,Qiuyan Liu,Jingming Ning
In this study, the stems (ST) and leaves (LT) isolated from Large-leaf yellow tea (LYT) were used for sensory evaluation and quantitative analysis of flavor metabolites by sensomics and flavoromics. The results showed that the flavors of ST and LT in LYT were significantly different, and ST had stronger roasty and nutty aroma and sweet taste, which was mainly due to the accumulation of higher theanine and soluble monosaccharides in ST, and provided more substrates for the production of more pyrazine by the Maillard reaction; whereas LT contributed to the mellow and thick taste quality of LYT, and the abundance of catechins and caffeine were the main reason. The metabolic patterns of flavor metabolites indicated that the flavor differences between ST and LT were mainly due to biological metabolism in tea plants. This study provides the selection of raw materials for LYT in the future and product development of tea stems.
研究领域:
食品科学
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茶叶科学
·
农业化学
·
感官评价
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
·
2023
·Vol. 103
·期 10
·4993-5003
·
IF 4.1
Fengnan Li,Isaac D Boateng,Xiao-Ming Yang,Yuanyuan Li,Weimin Liu
BACKGROUND Ginkgo biloba leaves contain beneficial flavonoids, bilobalide (BB), and ginkgolides. However, the toxic ginkgolic acid (GA) limit its application. In this study, various traditional processing methods were used to prepare G. biloba leaf tea (GBLT), including white tea, black tea, dark tea, green tea, and freeze-dried as control, followed by investigations of their effects on quality, antioxidant capacity, bioactive components, and cytotoxicity of the tea products. RESULTS Results showed that different processing methods significantly impact the tea products' quality indexes and the principal component analysis (PCA) and hierarchical cluster analysis (HCA) corroborated it. White tea had the highest total sugar (TS) and GA content and the most potent cytotoxicity on HepG2 cells. However, TS and GA content and the cytotoxicity of GBLT markedly decreased during fermentation and fixation. Moreover, white tea possessed higher total phenolic content (TPC), total flavonoid content (TFC), and more vigorous antioxidant activities than green tea, black tea, and dark tea. Terpene trilactones value was stable, but different catechins contents fluctuated according to the manufacturing process of different GBLTs. Among the four GBLTs, dark tea combining fixation and fermentation had the lowest GA content and cytotoxicity, less bioactive components reduction, appropriate quality, and stronger flavor. CONCLUSION These findings demonstrate that fixation and fermentation help reduce GAs during the manufacturing of GBLT. However, their ability to retain bioactive substances needs further optimization in future studies. © 2023 Society of Chemical Industry.
研究领域:
食品科学
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药理学
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生物化学
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产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2023
·
IF 8.1
Yujiao Sun,Xushuang Yuan,Zhaojun Luo,Yungang Cao,Shuai Liu,Yang Liu
Liquid-state fermentation (LSF) of tea leaves is a promising way to obtain tea-based nutraceutical products rich in various bioactive compounds. In the study, the changes of bioactive compounds, tea pigments and complex metabolites from LSF of primary dark tea, green tea and white tea infusions with Aspergillus cristatus were determined. Chemical analyses revealed that soluble sugars, monosaccharide composition, total polyphenols, total flavonoids, free amino acids, soluble proteins and tea pigments were changed in different ways. An untargeted metabolomic analysis and ribonucleic acid sequencing (RNA-seq) based transcriptomic analysis were performed to investigate the metabolic differentiation and clarify the key differentially expressed genes (DEGs, fold change >2 and p < 0.05), showing that amino acid metabolism, carbohydrate metabolism and lipid metabolism were the most enriched pathways during A. cristatus fermentation of primary dark tea, green tea and white tea infusions. In addition, glycerophospholipid metabolism, linoleic acid metabolism and phenylalanine metabolism were greatly accumulated in the fermentation of primary dark tea and white tea infusions; Pyruvate metabolism, glycolysis/gluconeogenesis, fatty acid degradation, tyrosine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis and valine and leucine, isoleucine degradation were greatly accumulated in the fermentation of primary dark tea and green tea infusions; Starch and sucrose metabolism was greatly accumulated in the fermentation of green tea and white tea infusions; Galactose metabolism was significantly enhanced in the fermentation of primary dark tea infusion; Amino sugar and nucleotide sugar metabolism, sphingolipid metabolism and alanine, aspartate and glutamate metabolism were significantly enhanced in the fermentation of green tea infusion. Besides, some other pathways involving aminobenzoate degradation, biosynthesis of cofactors, pyrimidine metabolism, benzoxazinoid biosynthesis and phenazine biosynthesis, tropane, piperidine and pyridine alkaloid biosynthesis and flavone and flavonol biosynthesis also differed from each other. These findings support that A. cristatus plays a vital role in the biochemical and genetic regulation of metabolite profile, and could be considered a potential prospect for better use of A. cristatus on different kinds of tea materials.
研究领域:
食品科学
·
微生物学
·
分子生物学
·
营养保健品
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产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2022
·
IF 6.056
Lijuan Ma,Yuxi Peng,Liping Du,Linqi Zhang,Wenzhe Tong,Yanru Weng,Dongguang Xiao,Huiling Zhang,Jihong Huang
As a typical Chinese tea, Pu-erh tea attracts much attention due to its unique flavor formed by taste and aroma compounds. To study the effects of taste compounds on the aroma release, model solutions containing five typical methoxyphenolic compounds (MCs) and main taste compounds with different concentrations were prepared based on the analysis of Pu-erh tea samples. GC-MS results indicated that the release of five MCs was inhibited by theabrownin, tea polysaccharide, tea polyphenol and catechins. The release of 1,2-dimethoxybenzene, 3,4-dimethoxytoluene and 1,2,3-trimethoxy-5-methyl-benzene was promoted by gallic acid under a low concentration (≤4 mg/g). Statistically, gallic acid had the most significant effect on the release of MCs. Isothermal titration calorimetry suggested that hydrogen bonds and hydrophobic effects had potential contributions to the interaction between taste and aroma compounds. This work will provide the research basis for revealing the formation mechanism of tea flavor.
研究领域:
食品科学
·
化学
·
农业科学
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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）