FOOD CHEMISTRY
·
2021
·
IF 7.514
Qing-Qing Cao,Fang Wang,Jie-Qiong Wang,Jian-Xin Chen,Jun-Feng Yin,Lijun Li,Fan-Ke Meng,Yong Cheng,Yong-Quan Xu
The effects of brewing water on the sensory attributes and physicochemical properties of tea infusions made from Chinese teas were investigated. The tea infusions brewed in water with higher pH and total dissolved solids (TDS), generally had a darker color and lower overall sensory acceptability. Moreover, those infusions had less catechins, particularly galloylated-catechins, and lower antioxidant capacity. The teas with less fermentation contained more galloylated-catechins and had higher antioxidant capacity, but were much more susceptible to high mineral brewing water. Green tea was proved to be the most susceptible one, whereas dark tea the most stable one. Green tea infusions prepared with higher pH/TDS water were more rapidly oxidized, resulting in a darker color due to polymerization of catechins, when exposed to the air. These findings suggested that low mineral brewing water was better for Chinese tea, both from the sensory and health benefit perspectives.
研究领域:
食品科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2020
·Vol. 25
·期 18
·4076
·
IF 3.267
Lin Chen,Wei Wang,Jianyong Zhang,Weiwei Wang,Dejiang Ni,Heyuan Jiang
Although tea catechins in green tea and green tea beverages must be stable to deliver good sensory quality and healthy benefits, they are always unstable during processing and storage. Ascorbic acid (AA) is often used to protect catechins in green tea beverages, and AA is easily oxidized to form dehydroascorbic acid (DHAA). However, the function of DHAA on the stability of catechins is not clear. The objective of this study was to determine the effects of DHAA on the stability of catechins and clarify the mechanism of effects by conducting a series of experiments that incubate DHAA with epigallocatechin gallate (EGCG) or catechins. Results showed that DHAA had a dual function on EGCG stability, protecting its stability by inhibiting hydrolysis and promoting EGCG consumption by forming ascorbyl adducts. DHAA also reacted with (−)-epicatechin (EC), (−)-epicatechin gallate (ECG), and (−)-epigallocatechin (EGC) to form ascorbyl adducts, which destabilized them. After 9 h of reaction with DHAA, the depletion rates of EGCG, ECG, EC, and EGC were 30.08%, 22.78%, 21.45%, and 13.55%, respectively. The ability of DHAA to promote catechins depletion went from high to low: EGCG, ECG, EGC, and EC. The results are important for the processing and storage of tea and tea beverages, as well as the general exploration of synergistic functions of AA and catechins.Keywords:catechins;ascorbic acid;dehydroascorbic acid;stability;mechanism
研究领域:
食品科学
·
化学
✓ 已验证
DOI
PubMed
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
·
茶叶化学
·
酶学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2016
·Vol. 21
·期 10
·1345
·
IF 2.465
Meng Shi,Ying Nie,Xin-Qiang Zheng,Jian-Liang Lu,Yue-Rong Liang,Jian-Hui Ye
Ultraviolet B (UVB) photosensitivities of eight catechins were screened. In both water and ethanol, epicatechin (EC, 575 μM) and catechin (C, 575 μM) exhibited low photostabilities under 6 h UVB radiation with the generation of yellow photoproducts, while other catechins (epigallocatechin gallate, epigallocatechin, epicatechin gallate, gallocatechingallate, gallocatechin, catechin gallate) were relatively UVB-insensitive. Photoisomerization and photolysis were two important UVB-induced reactions to EC whereas photolysis was the dominant reaction for C. The influencing factors of time (2–10 h), solvent (water, ethanol) and substrate concentration (71.875–1150 μM) on UVB-induced chemical conversions of EC and C were investigated, and eight photoproducts were identified through ultra performance liquid chromatography-diode array detection-tandem mass spectrometry (UPLC-DAD-MS/MS) and1H nuclear magnetic resonance (1H-NMR analysis). Photolysis reaction involved two pathways, including radical reaction and photo-induced electron transfer reaction. The 2,2-diphenylpicrylhydrazyl (DPPH) scavenging abilities of eight catechins did not change upon 6 h UVB irradiation. EC and C are photosensitive catechins among eight catechins causing deep color.Keywords:photostability;catechins;photoisomerization;photolysis;photoproducts
研究领域:
食品科学
·
植物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2025
·
IF 8
Qing Zhang,Mengdi Wang,Junfeng Hu,Shan Jiang,Yuemeng Xu,You Long,Liang Zhang,Min Xi,Yi Chen,Mengting Zhu
This study systematically investigated the inhibitory effects of catechins including (−)-epigallocatechin gallate (EGCG), epicatechin gallate (ECG), (−)-epicatechin (EC), and (−)-epigallocatechin (EGC) on furan formation during thermal oxidation (150 °C, 30 min) of linoleic acid, a major unsaturated fatty acid in vegetable oils. All catechins, tested at linoleic acid: catechins molar ratios of 10:1 to 1:1, demonstrated dose-dependent suppression of furan and volatile aldehydes formation, except EC/ECG at 10:1 which promoted formation of the critical furan intermediate, ( E,E )-2,4-decadienal. The inhibitory effects of the four catechins on 2,4-decadienal levels largely matched their efficacy in reducing furan generation. Among the catechins, EGCG exhibited the most potent inhibitory activity. It significantly suppressed both furan generation and the formation of the key ( E,E )-2,4-decadienal intermediate during linoleic acid heating (150 °C, 0–120 min) compared to the control ( P < 0.05 ). Mechanistic investigations revealed that EGCG reduced linoleic acid degradation by 47.3 % versus the control, as quantified by 1 H NMR analysis. Electron paramagnetic resonance (EPR) spectroscopy further demonstrated that EGCG significantly attenuated the formation of alkyl radicals, indicating interference with radical chain propagation. Crucially, liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (LC-QTOF-MS/MS) analysis, supported by computational modeling, confirmed the absence of covalent adduct formation between EGCG and either linoleic acid or 2,4-decadienal. These results indicate that EGCG primarily suppresses ( E,E )-2,4-decadienal generation by delaying linoleic acid oxidation via quenching radical chain reactions, thereby reducing furan formation. The findings highlight the potential of catechins, particularly EGCG, for mitigating harmful thermal oxidation processes in vegetable oils during food processing.
研究领域:
食品化学
·
脂质氧化
·
天然产物
·
抗氧化机制
·
热加工
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2015
·
IF 3.391
Fang-Yuan Fan,Meng Shi,Ying Nie,Yue Zhao,Jian-Hui Ye,Yue-Rong Liang
Tea catechins as a member of flavan-3-ols subclass with the same skeleton may behave differentially. This study investigated the chemical conversions of 8 catechins under heat treatment with the involvement of epimerization, hydrolysis and oxidation/condensation reactions. Three reactions were enhanced as temperature increased from 30 °C to 90 °C. The epimerization of non-gallated catechins was favored by epi-configuration but hindered by pyrogallol moiety, and the hydrolysis reaction of gallated catechins was facilitated by pyrogallol moiety. Epicatechin and epigallocatechin had the lowest thermostabilities due to epimerization and oxidation/condensation reactions respectively. Sufficient O 2 was not a precondition for the occurrence of chemical conversions of catechins under heat treatment. Non-enzymatic oligomerization occurred to epi type catechins and catechin under heat treatment, and dehydrodicatechins A were mainly responsible for the browning of epicatechin and catechin solutions. The evidence of generation of catechin oligomers provides a novel way to explain sensory change of tea and relevant products during thermal processing.
研究领域:
食品科学
·
植物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Foods
·
2022
·Vol. 11
·期 9
·1273
·
IF 5.561
Jie-Qiong Wang,Ying Gao,Dan Long,Jun-Feng Yin,Liang Zeng,Yan-Qun Xu,Yong-Quan Xu
Hydrogen peroxide has a significant effect on the flavor of tea beverages. In this study, the yield of hydrogen peroxide in (–)-epigallocatechin gallate (EGCG) solution was first investigated and found to be significantly enhanced under specific conditions, and the above phenomenon was amplified by the addition of linalool. Then, an aqueous hydrogen peroxide solution was added to a linalool solution and it was found that the concentration of linalool was significantly reduced in the above-reconstituted system. These findings were verified by extending the study system to the whole green tea infusions. The results suggested that the production of hydrogen peroxide in tea beverages may be dominated by catechins, with multiple factors acting synergistically, thereby leading to aroma deterioration and affecting the quality of tea beverages. The above results provided a feasible explanation for the deterioration of flavor quality of green tea beverages with shelf life.Keywords:green tea beverages;EGCG;hydrogen peroxide;linalool;flavor
研究领域:
食品科学
·
化学
·
饮料技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2025
·
IF 2.5
Feng-Yang Chen,Xia Tang,Yuan Zhu,Hang Li,Baoru Yang,Qinghai Sheng,Qing‐Sheng Zhao
Catechin (C) is a flavonoid natural polyphenol with a variety of biological activities; however, it has a poor solubility, stability and oral bioavailability, which greatly limits its application in food and medical fields. Unlike ordinary cyclodextrins, As a hyperbranched polymer, hyperbranched cyclodextrin( CDP) has some remarkable characteristics of hyperbranched polymers, such as a high degree of molecular branching, abundant active ends, and a macromolecular structure with multiple cavities. These features give CDP unique advantages in a variety of applications. In this study, catechin/hyperbranched cyclodextrin inclusion complex (Catechin/CDP IC) and catechin/β-cyclodextrin inclusion complex (Catechin/β-CD IC) were prepared by freeze-drying method at a molar ratio of 1:1. The embedding efficiency (CE) of the two inclusion complexes were 83. 85%, and 64. 85% respectively. The structural characterization was carried out via FT-IR, XRD, SEM, DSC and 1H NMR analyses. Furthermore, the results of solubility, thermal stability, storage stability, sustained-release characteristics, cell viability, antioxidant capacity and antibacterial ability of catechin complexed with CDP were better than that complexed with β-CD. This study provides a potential application value for the further development of catechin-based functional foods and health products.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2025
·
IF 6.6
Tinglan Yuan,Ting Ye,Haitao Guo,Yaoruixi Yang,Gongshuai Song,Danli Wang,Ling Li,Yong Cheng,Jinyan Gong
Complexes formed between polyphenols and proteins could be used as a good alternative to improve the phytochemical stability in food matrices. While interactions between tea catechins and milk proteins are prevalent in food systems, the effects of different structures of catechins on these interactions, and the resulting alterations in structural and functional properties of covalent complexes formed remain poorly understood. This study investigated the effect of different catechin structures on covalent interactions with β-lactoglobulin (β-Lg). (+)-Catechin (C), (−)-epicatechin (EC), (−)-epigallocatechin (EGC), (−)-epicatechin gallate (ECG), (−)-gallocatechin gallate (GCG), and (−)-epigallocatechin gallate (EGCG) were covalently bound to β-Lg through the alkaline method. β-Lg-catechin complexes had lower fluorescence intensity, hydrophobicity, α-helix content, free amino groups, and sulfhydryl groups than native β-Lg. Binding to catechins (especially ECG, GCG, and EGCG) significantly enhanced β-Lg antioxidant activity, emulsification activity, and stability. Furthermore, β-Lg-catechin complexes substantially enhance emulsion freeze-thaw, thermal stability, storage stability, and oxidative stability. Galloylated catechins exhibited the greatest graft affinity towards β-Lg, and their complexes demonstrated far superior antioxidant activity and stability than non-galloylated catechins. In conclusion, customized β-Lg-catechin conjugates have considerable potential as carriers in food that can enhance emulsion phytochemical stability.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
Analytical Methods
·
2025
·
IF 2.6
Lijun Yang,Zhiyi Zhang,Tiantian Zhou,Wei Qi,Mengfan Wang
In this study, a nanozyme-based sensor array was developed to achieve the identification and discrimination of three catechins (catechin, epicatechin, and epigallocatechin). The Fc@ZIF-67 NC nanozyme was synthesized with oxidase-like activity through the high-temperature carbonization of ferrocene-encapsulated ZIF-67. Two Fc@ZIF-67 NC-involved oxidase-like reactions were designed to generate three detectable signals (including two colorimetric signals and one fluorescent signal), which constituted the fingerprints of the analytes. By combining with linear discriminant analysis (LDA), different kinds and concentrations of catechins can be discriminated with this sensor array. Besides, the sensor array was proved feasible in the identification of catechins in real samples. This method provides a promising methodology for the discrimination and identification of natural products in food.
研究领域:
食品科学
·
分析化学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Current Research in Food Science
·
2024
·
IF 6.2
Ruiwei Xie,Haolin Zhang,Xiaomei Lv,Qiuyi Lin,Bing-Huei Chen,Yu-Wen Lai,Lei Chen,Hui Teng,Hui Cao
The favorable inhibitory effect of tea polyphenols on heterocyclic aromatic amines (HAAs) has been confirmed in many past studies. The objective of this study was to investigate the structure-activity relationship of catechins that act as inhibitors of HAA formation in chemical models. Two kinds of quantitative structure-activity relationship models for catechin-inhibiting-HAA were established. We chose two kinds of HAAs including 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and five catechins including epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC), epicatechin (EC), and catechin (C). The inhibitory effect of five catechins were in the following order: EGCG > ECG > EGC > C > EC. Thereinto, EGCG and ECG showed dramatically better inhibition on the formation of PhIP and MeIQx, especially EGCG. Further, the mechanisms of catechin-inhibiting-HAA were speculated by correlation analysis. The free radical-scavenging ability was predicted to be the most relevant to the inhibitory effect of ECG, EGC, EC and C on HAAs. Differently, the phenylacetaldehyde-trapping ability might be the more important mechanism of EGCG inhibiting PhIP in chemical model system. This study may bring a broader idea for controlling the formation of HAAs according to the structure of catechins.
研究领域:
食品科学
·
生物化学
·
营养学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2022
·
IF 6.556
Meini Li,Yunfei Xie,Donghui Song,Hui Huang,Yongxin Li
In this work, 2-methylimidazole (MI) was doped into the Bpy-Cu nanozyme as a second ligand to form a novel laccase-mimicking enzyme (MI-Bpy-Cu). By comparison, MI-Bpy-Cu nanozyme was identified to have excellent laccase-mimicking activity, high stability and catalytic kinetic properties. It may be that the incorporation of 2-methylimidazole helped the nanozymes to build a structure closer to natural laccase and accelerate the electron transfer rate, thereby achieving the purpose of enhancing the activity. Furthermore, we observed that MI-Bpy-Cu nanozymes could oxidize the colorless (+)-Catechin to generate a yellow radical product, and a novel colorimetric sensing strategy for (+)-Catechin was successfully developed. The method had excellent selectivity and anti-interference properties, and also had good application in the analysis of (+)-Catechin in dairy products.
研究领域:
纳米技术
·
分析化学
·
食品科学
✓ 已验证
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）