JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2023
·
IF 4.3
Chunyin Qin,Zongde Jiang,Asma Parveen,Mengting Zhu,Mingchun Wen,Liang Zhang
Black tea cream down can be separated into the resoluble (RS) and irresoluble (IS) parts. The irresoluble part hardly dissolves in boiling water after it forms in tea infusion, thus it is an indelible particle in the tea beverage industry. In the current work, we qualitatively and quantitatively analyzed the differences of chemical composition between these two parts. The results showed that the irresoluble cream down contained theaflavins and caffeine, but only dissolved in DMSO rather than boiling water. The irresoluble cream down contained higher levels of Al , Ca, Fe, and Cu mineral elements than resoluble cream down. The elemental analysis also indicated that irresoluble cream down was composed of more hydrogen element than resoluble cream down. The Fourier transform infrared (FT-IR) spectroscopy analysis confirmed that the irresoluble cream down spectrum presented two critical differential absorption peaks at 2919 and 2850 cm −1 , which were attributed to the saturated carbon moiety of organic compounds. Moreover, we compared the effects of four metal ions (including Al 3+ , Ca 2+ , Fe 3+ , and Cu 2+ ) on the formation of cream particle, and found that Al 3+ had the strongest contribution to the particle formation of cream down. Meanwhile, caffeine also contributed to the particle formation of cream down as a secondary role.
研究领域:
食品科学
·
分析化学
·
茶叶科学
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产品关联
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2025
·
IF 8
Ting Huang,Yinggen Zhang,Xiuping Wang,Hui Zhang,Changsong Chen,Quanbin Chen,Qiusheng Zhong
Ming guan’(MG), an elite albino cultivar deriving from the progeny of the traditional albino cultivar ‘Bai jiguan’, is a promising candidate for white tea production due to its favorable amino acid to phenol ratio. In this study, a comprehensive metabolomics analysis using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) and headspace solid-phase microextraction-gas chromatography mass spectrometry (HS-SPME-GC–MS) were conducted to reveal the dynamic changes of non-volatile and volatile organic compounds (VOCs) throughout the withering processing of MG white tea. Meanwhile, multivariate statistical analyses were applied to screen for the characteristic components in the flavor and aroma of MG white tea. A total of 625 non-volatile metabolites and 118 VOCs were determined, of which 90 non-volatile metabolites (VIP ≥ 1, FC ≥ 2 or ≤ 0.5) were identified as key flavor components significantly changed throughout the withering process. The relative odor activity value (ROAV) analysis highlighted 22 VOCs (ROAV ≥ 1) with substantial effect on aroma formation, of which geraniol, (E)-2-hexenal, 4-methoxy-benzaldehyde and guaiacol emerging as the most key aroma constituents of MG white tea, endowing MG white tea with fruity and floral odor notes. This study offered a comprehensive investigation into metabolite changes in MG white tea, contributing valuable insights for the innovation of new white tea products utilizing albino tea plant mutants.
研究领域:
植物学
·
食品科学
·
代谢组学
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2024
·
IF 2.7
Xuancheng Wang,Zhiyong She,Hailin Zhou,Tingting An,Jianwen Teng,Ning Xia,Pingchuan Zhu,Wenhui Liu,Huanxiao Dong,Limin Tang,Shulan You,Lu Wei,Kongying Li,Lingli Wang,Li Huang,Qisong Zhang
Liupao tea (LPT) is a Chinese dark tea known to possess a unique flavour. Microbial fermentation plays a crucial role in flavour development and enrichment. Currently, the phytochemical profiles and bioactivities of LPT with and without fermentation are not fully known. In this study, we compared the chemical composition of raw tea (SF), stale-aroma (SA), and betelnut-aroma (BA) type LPT through the application of GC/LC-MS-based metabolomics, and experimentally investigated their bioactivities via antioxidant, anti-inflammatory, hypolipidemic, and hypoglycemic assays in vitro. The results indicated that fermentation enhanced the flavour of LPT as evidenced by the sweetness-producing substances, decreased bitterness and astringency-related compounds and enriched abundance of aroma-generating compounds. Two and four volatiles were detected to be major contributors to the aroma in SA and BA, respectively. Fatty acids and phosphatidylcholines were the primary lipids, among which the lysing diacylglycerol trimethyl homoserines were found to be a new class of lipids in LPT. Notably, the fermentation resulted in the degradation of compounds, particularly glycerophospholipids and saccharolipids. SF had the highest level of bioactivity, followed by BA and SA. These findings expand the present understanding regarding the development of flavour, nutrition, and medicinal value of LPT. Moreover, they provide a theoretical basis for the identification of BA and SA and serve as a reference value for consumers in their selection of LPT products.
研究领域:
食品科学
·
药理学
·
代谢组学
·
茶叶科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2020
·
IF 4.192
Zhongyu Li,Yan Mao,Jianwen Teng,Ning Xia,Li Huang,Baoyao Wei,Qingjin Chen
Citrinin (CIT), a known nephrotoxic mycotoxin, is mainly produced by Penicillium, Aspergillus, and Monascus species. It is a natural contaminant in cereal grains, foods, and feedstuff. Liupao tea (or Liubao tea) is a typical Chinese dark tea obtained via indigenous tea fermentation facilitated by microorganisms. Certain fungi present in Liupao tea that may produce CIT are a potential threat to consumer health. In the present study, various potential toxigenic mycoflora and the natural occurrence of CIT in Liupao tea were surveyed via the culture-dependent method, high performance liquid chromatography–fluorescence detection (HPLC–FLD), and ultrahigh performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). Total mold counts ranged from 3.5 × 102 CFU/g to 2.1 × 106 CFU/g tea in 28 tea samples. A total of 218 fungal isolates belonging to five genera and 23 species were identified. Some of these strains, such as Aspergillus ochraceus, Aspergillus oryzae, Penicillium citrinum, and Penicillium chrysogenum, may potentially be a CIT-producing species. In addition, 32.7% of 113 Liupao tea samples were contaminated with CIT at concentrations ranging from 7.8 to 206.1 μg/kg. These CIT concentrations in Liupao tea are chiefly attributed to climatic conditions and water activity during storage that favor fungal proliferation and mycotoxin production. However, CIT could not be detected in Liupao tea stored for over 10 years. These results provide the first information about the potential toxigenic mycoflora and natural occurrence of CIT in Liupao tea. Therefore, storage conditions and fungal community must be monitored to ensure the quality of Liupao tea.
研究领域:
食品安全
·
微生物学
·
植物学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2019
·
IF 3.571
Xiaoqiang Chen,Yuntian Zhang,Yu Han,Qian Li,Li Wu,Jia Zhang,Xiaoling Zhong,Jianchun Xie,Shengrong Shao,Yinjun Zhang,Zhengqi Wu
Chin-brick tea polysaccharide conjugates (TPC-C) were prepared to study their emulsion capabilities. Interfacial tension and the effects of some factors, such as storage time, metal ion concentrations (Na+, Ca2+), pH (2.0–8.0), and heat treatment (70–100 °C) on the emulsions stabilized by TPC-C were studied. The interfacial tension of TPC-C (10.88 mN/m) was lower than that of gum arabic (15.18 mN/m) at a concentration of 0.08%. As the TPC-C concentration increased from 0.1 to 3.0 wt %, the mean particle diameter (MPD) (d32) of emulsions stabilized by TPC-C decreased from 1.88 to 0.16 μm. Furthermore, at a concentration of 0.5 wt % or higher, the MPD (d32) of emulsions stabilized by TPC-C at 25 and 60 °C for 10 days was between 0.20 and 0.50 μm. In the tested pH conditions from 2.0 to 8.0, the MPD (d32) of emulsions stabilized by 2.0 wt % TPC-C was less than 0.20 μm. At Na+ concentration conditions between 0.10 and 0.50 mol/L, the MPD (d32) of emulsions was between 0.19 and 0.20 μm, and the zeta potential values varied from −34.10 to −32.60 mV. However, with an increasing Ca2+ concentration from 0.01 to 0.05 mol/L, the MPD (d32) of emulsions was between 0.20 and 21.65 μm, and the zeta potential raised sharply from −34.10 to −28.46 mV. The emulsions stabilized by TPC-C have a decent storage stability after a high-temperature heat treatment. Overall, tea polysaccharide conjugates strongly stabilized the emulsions, which support their new application as natural emulsifiers.
研究领域:
食品科学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Jun Zeng,Gang Du,Xue Shao,Ke-Na Feng,Ying Zeng
Theaflavins (TFs) have attracted much attention due to their various bioactivities in black tea. This paper describes the first trial for enzymatic production of TFs by recombinant polyphenol oxidases (PPOs). PPO genes were cloned from nine species and expressed in E. coli . Crude enzyme assays by LC-MS revealed that eight recombinant PPOs were active for TFs production from tea polyphenols as substrates. Much higher activities were observed for crude enzymes of Md2 from Malus domestica (apple), Pp4 from Pyrus pashia (pear), and Ej2 from Eriobotrya japonica (loquat). When immobilized on mesoporous silica, crude Md2 was most active. The purified Md2 was immobilized and showed almost twice activity as high as its free enzyme. While the maximum activity of free enzyme was found at pH 5 and 10–30 °C, the immobilized enzyme had broader range of pH 4–6 and 10–40 °C. The activity of immobilized enzyme was relatively constant during the pH and thermal stability test. When used at 0.2 mg/ml in the beginning, the immobilized enzyme retained approximately 40% of its initial activity after 8 cycles of operation.
研究领域:
生物技术
·
酶学
·
食品科学
·
植物生化
✓ 已验证
DOI
PubMed
高影响因子
CELLULOSE
·
2022
·Vol. 29
·期 17
·9089-9104
·
IF 6.123
Zhao Yang,Jin Bo,Zheng Tian,Peng Rufang
A novel natural macromolecule stabilizer, tea polyphenol, was developed based on the scavenging effect of nitroxide radical to enhance the thermal stability of nitrocellulose. The structural of tea polyphenols was confirmed by infrared spectroscopy, and their good thermal stability of tea polyphenols in nitrocellulose was confirmed by methyl violet paper test and vacuum stability test. The iso-thermogravimetric test showed that tea polyphenols could prolong the safe storage life of nitrocellulose. The inhibition of tea polyphenols on the autocatalytic thermal decomposition of nitrocellulose in the early stage of nitrocellulose thermal decomposition was confirmed by SEM images at different stages of nitrocellulose thermal decomposition. The thermal interaction between tea polyphenols and nitrocellulose was further analyzed by non-isothermal thermal analysis. Experiments confirmed that tea polyphenols can enhance the thermal stability of nitrocellulose. Their addition increased the T 0 of nitrocellulose by 2.0–9.4 ℃, the T bp 0 by 1.4–9.6 ℃, and the activation energy of nitrocellulose by 5.38–9.77 kJ·mol –1 .
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Food Bioscience
·
2019
·
IF 3.22
Weilu Guo,Mouming Zhao,Qingjin Chen,Li Huang,Yan Mao,Ning Xia,Jianwen Teng,Baoyao Wei
The ability of a strain to produce citrinin was analysed in the growth inhibition zone using HPLC and UHPLC–MS. A total of 12 Penicillium citrinum strains isolated from Liupao tea were inoculated onto tea leaves and their capability for citrinin production were studied using different water content (15–45%) and temperatures (15–40 °C). The results provided a theoretical base for the safe manufacture of Liupao tea. Five strains of P. citrinum produced a clear growth inhibition zone with diameters of 11–22 mm. The citrinin contents in the liquid cultures of the 12 strains of P. citrinum ranged from 0.03 to 14.5 μg/mL. The citrinin contents of the teas with initial water content of 15 and 25% and those inoculated with P. citrinum were below the limit of detection during the fermentation. The citrinin content of the teas with initial water contents of 35 and 45% at 25 °C increased rapidly at first and then decreased during the fermentation. Similarly, the citrinin contents of the teas at 15 and 25 °C rapidly increased and then decreased. Meanwhile, P . citrinum was unable to produce citrinin at 35 and 40 °C. The optimum conditions were 45% water and 25 °C, generating the highest citrinin yield of 181 ng/g, which was higher than the limit of 50 ng/g citrinin in red yeast rice that can cause harm to human health. The highest citrinin yield in tea fermented for 50 days was 34.8 ng/g for stored teas with proper conditions. Therefore, storing teas with a low water content and temperature can reduce the content of citrinin.
研究领域:
食品科学
·
微生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF FOOD PROCESSING AND PRESERVATION
·
2020
·Vol. 44
·期 5
·e14433
·
IF 1.405
Mai-Rui Gao,Qian-Da Xu,Wei-Cai Zeng
The effect and action mechanism of tea polyphenols (TP) on the tenderness of yak meat were investigated. With the treatment of TP at the low concentrations, the myofibril fragmentation index (MFI) value of yak meat was increased and its microstructure was obviously changed. By using fluorescence spectroscopy and the determination of surface hydrophobicity, the tertiary structure of myofibrillar protein (MP) showed the obvious changes with the treatment of epigallocatechin gallate (EGCG). In addition, the secondary structure of MP was also obviously changed according to the measurement of circular dichroism (CD) spectrum, while the α-helix structure of MP decreased and the β-sheet increased. Furthermore, according to the analysis of molecular docking, EGCG could interact tightly with myofibril protein by hydrogen bonds, and changed its spatial configuration and molecular force. All results suggested that TPs showed the potentially value to improve the tenderness of yak meat in food industry. Practical applications Yak meat is more and more popular by its high nutrition value. But due to its special myofibril protein, the tenderness of yak meat is unfavorably and affects its sensory properties, which may limit its processing and consumption in food industry. In present study, TPs was used to improve the tenderness of yak meat by changing the spatial configuration and molecular force of myofibril protein, which suggested that TPs showed the potential value to enhance the quality of yak meat during its processing in food industry.
研究领域:
食品科学
·
生物化学
✓ 已验证
DOI
高影响因子
Foods
·
2025
·Vol. 14
·期 9
·1552
·
IF 5.1
Yuqin Xiong,Haomu Liao,Haiyue Liao,Xiaoyue Song,Chunhua Ma,Yan Huang
This study enhanced the odor retention of instant black tea powder by utilizing ultrasonic-assisted extraction and β-cyclodextrin embedding technology. Through single-factor tests considering variables such as the tea-to-water ratio, extraction temperature, ultrasonic extraction duration, and β-cyclodextrin addition, the optimal extraction conditions were determined. The ideal parameters were identified as follows: β-cyclodextrin was added at a rate of 7.5%, the tea-to-water ratio was 1:16, the ultrasonic extraction temperature was 52 °C, and the extraction duration was 30 min, and then the extract was processed by freeze-drying to obtain instant tea powder. Electronic nose trials revealed that the primary volatile odor compounds distinguishing the 14 groups of instant black tea soups were sulfides, terpenes, nitrogen oxides, alkanes, and aromatic compounds. HS-SPME-GC-MS analysis identified 65 effective volatile compounds, among which 11 key odor compounds, including Benzyl alcohol, Phytol, phenylethyl alcohol, 1,6,10-Dodecatrien-3-ol,3,7,11-trimethyl-,(E)-, Benzeneacetaldehyde, Undecanoic acid, ethyl ester, Dodecanoic acid, ethyl ester, Tetradecane, 2,4-Di-tert-butylphenol, 2-Pentadecanone, 6,10,14-trimethyl-, and indole, were the main contributors to the odor profile of instant black tea. The instant black tea powder produced under these conditions exhibited high quality, providing a valuable reference for further research on the production process of instant black tea powder.
研究领域:
食品科学
·
化学工程
·
感官分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Hai-Biao Gong,Yue Ye,Shuo-Yan Tan,Qi Wang,Xiao-Yuan Gu,Chang-Yu Yan,Yu-Fei Wang,Yi-Ning Chen,Shi-Sheng Chen,Jian-Wen Ye,Wan-Yang Sun,Wei-Xi Li,Kun Li,Jing-Hao Wang,Hiroshi Kurihara,Yi-Fang Li,Rong-Rong He
Despite the known benefits of tea (Camellia sinensis), the functional potential of tea-derived proteins remains largely unexplored. To investigate this, tea proteins were extracted and enzymatically hydrolyzed with alkaline protease to obtain tea protein hydrolysates (TPH). Characterized by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), TPH were screened via integrated in silico and molecular docking for dual-action peptides targeting tyrosinase inhibition and antioxidant activity. Two peptides, EGFG and FGDPHG, were identified and validated as potential tyrosinase inhibitors and antioxidants, exhibiting strong free radical scavenging and iron-chelating capabilities in cell-free systems. In B16-F10 melanoma cells, both peptides significantly reduced α-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis and protected against hydrogen peroxide (H2O2)-induced oxidative stress. Their whitening efficacy was further confirmed in a zebrafish model. These findings establish EGFG and FGDPHG as novel, dual-action whitening peptides, highlighting their potential as functional ingredients in cosmetics and nutraceuticals.
✓ 已验证
DOI
PubMed
高影响因子
Food Bioscience
·
2024
·
IF 4.8
Weiwei Zhong,Weidi Yuan,Jiaying Wang,Zufang Wu,Hechao Du,Xianqing Huang,Yanan Liu
Tea polyphenols (TP), a natural ingredient recognized for their potent antioxidant and antimicrobial properties, are the focus for extending the freshness and shelf life of apple juices in preservation. This study evaluated the nutritional quality, microbial growth, and sensory changes in apple juice during storage, examining the impact of TP addition on both freshly pressed and retail high-pressure processing (HPP) apple juice. For fresh apple juice, the growth of total colonies was predicted using a modified Gompertz model. The results showed that the addition of 0.6 g/kg TP to fresh apple juice reduced the total number of colonies by 1.54 times after 11 days of storage, while the addition of 0.6 g/kg TP to retail HPP apple juice reduced the total number of colonies by 2.15 times after 20 days. In addition, apple juice treated with 0.6 g/kg of TP had good antioxidant and sensory properties compared to the control. These results indicated that the application of TP could increase the antioxidant capacity of apple juice, enhance their taste and prolong their shelf life.
研究领域:
食品科学
·
营养学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）