Foods
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2025
·Vol. 14
·期 11
·1894
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IF 5.1
Xiaomin Chen,Yao Hu,Zhen Zeng,Xu Zhang,Yahui Huang
As a potential raw material with a variety of bioactive compounds, Pu-erh raw tea can produce rich flavor and health benefits through natural fermentation or microbial fermentation in traditional processing. However, the traditional fermentation process has some problems such as a long fermentation period and unstable quality. Monascus, a kind of fungus used in both medicine and food, has been proved to have many beneficial effects such as lowering cholesterol and regulating blood lipids. Therefore, in this study we investigated whether the fermentation of mixed monascus could significantly improve the flavor quality and lipid-lowering activity of Pu-erh raw tea. We added four kinds of monascus to unfermented Pu-erh raw tea (UT) to obtain a fermented Pu-erh raw tea (FT). The quality of the two tea samples was determined and an in vitro lipid-lowering experiment was conducted. The results show that the contents of water extractives, flavone, trans-catechins (GCG and CG), theabrownins, and caffeine in FT are significantly higher than those in UT, increasing by 19.41%, 14.47%, 18.76%, 29.82%, and 10.67%, respectively. In terms of aroma, linalool was the characteristic compound of UT, presenting a floral note. D-Limonene was the key characteristic substance of FT, manifested as lemon, toast, and wood. In terms of taste, FT has a high content of bitter amino acids and caffeine, a low content of catechins, and is rich in carbohydrate substances, forming a characteristic mild and mellow slightly bitter taste with reduced astringency. In addition, the relative contents of active substances with lipid-lowering effects such as quercetin, quercitrin, ascorbic acid, and sorbitol in FT were higher than those in UT, increasing by 83.09%, 81.73%, 89.86%, and 92.76%, respectively. The effect of FT on regulating cellular lipid metabolism was superior to UT based on cell experiments. The research results provide a scientific basis for the deep processing and functional development of Pu-erh raw tea.
研究领域:
食品科学
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微生物学
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生物化学
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DOI
PubMed
高影响因子
ANALYTICAL LETTERS
·
2023
·
IF 2
Xinlei Zhang,Wenbao Jia,Xinru Tang,Qing Shan,Qiyan Chen,Can Cheng,Jinfa Shao,Yongsheng Ling,Daqian Hei
Teas of the same type in a small growing area are generally similar, and identification of their detailed geographic origin is challenging and interesting. In this study, a convenient method for distinguishing Pu-erh teas from nearby locations was developed by combining two spectroscopic techniques with chemometric methods. The distinction was based on the difference in the mineral elements and organic metabolites from tea infusions. First, Pu-erh tea was infused with water at 90 °C for 30 min. Total reflection X-ray fluorescence and ultraviolet-visible (UV-Vis) spectroscopies were used to determine the elements (P, S, K, Ca, Mn, and Ni) and organic metabolites (caffeine and polyphenols), respectively. Chemometric methods were applied to classify the origin based on the component. The proposed method was used to test samples collected from 10 mutually adjacent high-altitude villages in Mengku, Lincang, Yunnan, China. The developed user-friendly method was successfully used for the rapid evaluation of the composition, enabling the identification of the geographic origins of Pu-erh tea. Mn, caffeine, and polyphenols were found to be the key origin markers. Compared to principal component analysis, linear discriminant analysis models exhibited high discrimination performance with 100% predictive ability to distinguish the geographic origins of Pu-erh teas over a small production area. This rapid and simple method may be used to solve classification problems in tea quality control and management.
研究领域:
食品科学
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分析化学
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DOI
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Ting Ye,Hangbin Yan,Xu Wang,Weifan Zhao,Fang Tao,Yu Zhou
In daily tea drinking, little is known on aflatoxin transfers from tea-leaf to infusion during brewing and the actual intake. A verified aflatoxins analytical method on tea infusion is significant to the exposure assessment. Here, an optimal method 3 (M3) was screened and validated on four aflatoxins (B 1 , B 2 , G 1 and G 2 ) simultaneous determination. Recoveries of AFG 1 and AFB 1 were 87.37 %±1.99 %-102.03 %±8.62 %, and AFG 2 and AFB 2 were 83.99 %±8.65 %-100.14 %±1.69 %. The correlation coefficient on the fortified samples determination was > 0.99 for each aflatoxin. In accuracy and precision validation, aflatoxins recoveries in high and low fortified samples were 85.94 %-103.83 %, and RSDs were 2.20 %-9.15 %. Method applicability test showed that the M3 was qualified for six different dark tea types. Extraction rate of 30-days stored AFB 1 fortified tea-leaf by acetonitrile–water (84:16, v/v) was < 50 %; meanwhile, only 2.94 % spiked AFB 1 was released by ten times tea brewing which indicated that Puerh tea have strong adsorbability to aflatoxin.
研究领域:
食品科学
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分析化学
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DOI
PubMed
高影响因子
Food Chemistry-X
·
2023
·
IF 6.1
Yuting Rong,Jialing Xie,Haibo Yuan,Lilei Wang,Fuqiao Liu,Yuliang Deng,Yongwen Jiang,Yanqin Yang
Storage time is one of the important factors affecting the aroma quality of Pu-erh tea. In this study, the dynamic changes of volatile profiles of Pu-erh teas stored for different years were investigated by combining gas chromatography electronic nose (GC-E-Nose), gas chromatography-mass spectrometry (GC–MS), and gas chromatography-ion mobility spectrometry (GC-IMS). GC-E-Nose combined with partial least squares-discriminant analysis (PLS-DA) realized the rapid discrimination of Pu-erh tea with different storage time (R 2 Y = 0.992, Q 2 = 0.968). There were 43 and 91 volatile compounds identified by GC–MS and GC-IMS, respectively. A satisfactory discrimination (R 2 Y = 0.991, and Q 2 = 0.966) was achieved by using PLS-DA based on the volatile fingerprints of GC-IMS. Moreover, according to the multivariate analysis of VIP > 1.2 and univariate analysis of p < 0.05, 9 volatile components such as linalool and (E)-2-hexenal were selected as key variables to distinguish Pu-erh teas with different storage years. The results provide theoretical support for the quality control of Pu-erh tea.
研究领域:
食品科学
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分析化学
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DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2019
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IF 3.206
Liping Du,Chao Wang,Chenxia Zhang,Lijuan Ma,Yongquan Xu,Dongguang Xiao
Volatile compounds and sensory characteristics of instant Pu-erh teas (IPET) produced through the spray-drying process were evaluated by using headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS) and descriptive sensory analysis (DSA), and compared with Pu-erh tea (PET). A total of 208 and 204 volatiles were identified in IPET and PET, respectively. Through independent samples t -test, 98 and 55 compounds showed highly significant differences ( P ≤ 0.01) and significant differences (0.01 < P ≤ 0.05) between IPET and PET, respectively. Meanwhile, 158 compounds were defined to interpret the differences between IPET and PET using variable importance in the projection (VIP) value. Moreover，seven aroma attributes were identified through DSA. The results showed that IPET had the higher intensity of floral, fruity, sweet, and caramel-like descriptor, while PET demonstrated higher intensity of stale/musty and woody attributes.
研究领域:
食品科学
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分析化学
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DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2025
·Vol. 48
·期 4
·e70133
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IF 2.8
Wenting Li,Lunzhao Yi,Ying Gu,Dabing Ren,Wenjiang Dong
Ripened Pu-erh tea is a special tea with unique flavor and obtained by solid fermentation of microorganisms. This work aimed to investigate the changes of lipid metabolites during fermentation and the association between lipids and the aroma of ripened Pu-erh tea based on ultra-high-performance liquid chromatography-high resolution mass spectrometry and GC-MS. A total of 217 lipids and lipid-soluble substances covering 19 subclasses were detected and characterized. Compared with green tea, black tea, and raw Pu-erh tea, ripened Pu-erh tea showed the highest levels of fatty acids. The contents of 36 lipids varied remarkably with fermentation time, and thus these compounds were screened as differential metabolites. These changes were mainly caused by the degradation of glycerophospholipids (folds change: 0.48–0.13) and the formation of fatty acids (folds change: 5.2–11.2). Results of Pearson correlation analysis showed that a few of the aromatic volatiles, including 2-octenal, 3,5-octadien-2-one, 2,4-heptadienal, and 2,6-nonadienal showed obvious negative correlations with phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol, but significant positive correlations with fatty acids 18:2 and 18:1. This study provided a further understanding of the lipid composition of ripened Pu-erh and their changes during tea production.
研究领域:
食品科学
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代谢组学
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植物化学
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PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2020
·
IF 4.972
Chao Wang,Zhongrong He,Chenxia Zhang,Liping Du,Dongguang Xiao,Yongquan Xu
The objective of this study was to identify the released behavior of odor-active compounds of Pu-erh tea during the water-boiling extraction, as well as to explore the feasibility of aroma recovery using absorption oils. The behavior of odor-active compounds was identified by using piecewise recovered condensed water combined with sensory, GC-O, and GC–MS analysis. The power-function type kinetic model was the model that best fitted odor intensities, alcohols, methoxy-phenolics, esters, aldehydes, ketones, and total compounds of condensed water. The sensory quality of the condensed water was the best when 16% of added water was evaporated. Six absorption oils were evaluated, and paraffin oil (35 cSt) performed the best in terms of both absorption efficiency and sensory quality of the essential oil. Under the optimized conditions, the absorption and recovery efficiency of odor compounds reached 54.49% and 39.52%, respectively. The alcohols, aldehydes, and methoxy-phenolics exhibited higher absorption and recovery efficiency.
研究领域:
食品科学
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化学
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DOI
PubMed
高影响因子
JOURNAL OF PHARMACOLOGICAL AND TOXICOLOGICAL METHODS
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2014
·
IF 2.15
Juan Zhou,Yi-Qiao Xu,Sheng-Ya Guo,Chun-Qi Li
Introduction Hyperlipidemia is the most common form of dyslipidemia , which is the key risk factor for cardiovascular disease and stroke. The development of effective and safe drug treatments for hyperlipidemia has been proven challenging. Methods In this study, taking advantage of the transparency of larval zebrafish, we developed a zebrafish hyperlipidemia model for drug screening and efficacy assessment. Zebrafish at 5 d.p.f (days post fertilization) were fed with 0.1% egg yolk for 48 h (hours), followed by drug treatment for 24 h or 48 h. Tested drugs were administered into the zebrafish by direct soaking. Drug effect was evaluated based on quantitative analysis of Oil Red O (ORO) in zebrafish vena caudalis. Results All 5 human hypolipidemic drugs (simvastatin, lovastatin , ezetimibe , bezafibrate and hyodesoxycholic acid) showed significant hypolipidemic effects ( p < 0.01) in a dose-dependent manner in the zebrafish hyperlipidemia model. 'We also found a well-known Chinese tea Pu-erh tea significantly reduced lipids in this model ( p < 0.001 and p < 0.01). Discussion Our results demonstrate that the zebrafish hyperlipidemia model developed and validated in this study could be used for in vivo hyperlipidemia studies and drug screening and for assessing hypolipidemic drugs with different mechanisms.
研究领域:
药理学
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心血管疾病研究
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药物筛选
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DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
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2022
·
IF 6.056
Jirui Kun,Qing Meng,Chia-Cheng Wei,Guanhua Xie,Jingna Yan,Chi-Tang Ho,Huarong Tong
Cup aroma refers to the volatiles emitted from an empty cup after tea infusion. In this study, gas chromatography–olfactometry (GC–O) and the odor activity value (OAV) approach were employed to investigate the composition of fermented soybean-like cup aroma from raw Pu-erh tea. Further, the aroma recombination and omission tests were performed, and the results demonstrated that 2-methylbutyric acid, acetic acid, 4-methyl-3-penten-2-one, ethyl isobutyrate, nonanoic acid, and phenylacetic acid exhibited relatively high aroma intensities (AI) and OAVs among the 12 odor-active compounds that were detected in the fermented soybean-like cup aroma. The aroma recombination, which was performed employing the 12 odorants with AI ≥1 successfully mimicked the overall aroma profile of the fermented soybean-like cup aroma. The omission test revealed that 2-methylbutyric acid contributed significantly to the fermented soybean-like cup aroma. And the enantiomeric ratio (ER) of the ( S )- to ( R )-forms of 2-methylbutyric acid was 67:33.
研究领域:
食品科学
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分析化学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2022
·
IF 5.895
Tao Feng,Jiaqing Sun,Kai Wang,Shiqing Song,Da Chen,Haining Zhuang,Jun Lu,Dejun Li,Xianle Meng,Mingliang Shi,Lingyun Yao,Chi-Tang Ho
Steeping process is an important factor for aroma release of tea, which has rarely been investigated for the aroma changes of raw Pu-erh tea (RAPT). In addition, the comprehensive aroma characteristics identification of RAPT infusion is necessary. In this study, GC–IMS coupled with principal component analysis (PCA) was used to clarify the difference of volatile profiles during the steeping process of RAPT. Furthermore, the volatiles contained in the RAPT infusion were extracted by three pretreatment methods (HS-SPME, SBSE, and SAFE) and identified using GC–O–MS. According to the odor activity value, 28 of 66 compounds were categorized as aroma-active compounds. Aroma recombination and omission experiments showed that “fatty”, “green”, “fruity”, and “floral” are considered to be the main aroma attributes of RAPT infusion with a strong relationship with 1-octen-3-one, 1-octen-3-ol, (E)-2-octenal, β-ionone, linalool, etc. This study will contribute a better understanding of the mechanism of the RAPT steeping process and volatile generation.
研究领域:
食品科学
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分析化学
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DOI
PubMed
高影响因子
Food Chemistry-X
·
2025
·
IF 8.2
Zixi Yang,Yanxia Xie,Yuanmin Zhu,Mengjie Lei,Xuemin Chen,Wenwen Jin,Chunhua Fu,Longjiang Yu
Ripened Pu-erh tea (RPT) is renowned for its distinctive flavor and health benefits. However, its complex fermentation process poses challenges in ensuring consistency in production. This study investigated RPT flavor formation through sensory evaluation, multi-omics analysis, and multivariate statistical approaches. By day 24, the tea exhibited a reddish-brown infusion and a mellow, thick taste (MT_RPT), achieving the highest sensory score (94.0, P < 0.05). Sixteen flavor-related chemical components exhibited significant changes ( P < 0.05). The contents of free amino acids, L -theanine, tea polyphenols, flavonoids, catechins, and thearubigins decreased. In contrast, the contents of total soluble sugars, caffeine, theobromine, epicatechin, and theabrownins (TBs) increased, reaching 74.1 mg/g, 65.38 mg/g, 3.13 mg/g, 3.33 mg/g, and 134.84 mg/g, respectively. Additionally, 33 nonvolatile metabolites (e.g., pelargonidin 3-O-glucoside, dihydroisorhamnetin, and puerarin) were significantly correlated with MT_RPT flavor (VIP > 1, |r| ≥ 0.8, P < 0.05) and influenced by key functional microbes, including Pantoea , Aspergillus , Brachybacterium , and Staphylococcus . By day 30, the infusion darkened, and sensory scores declined (81.4, P < 0.05), attributed to the dominance of Brevibacterium . This microbial shift reduced water-soluble pectin, free amino acids, and 11 metabolites while increasing TBs and theophylline (219.33 mg/g and 0.09 mg/g, respectively). Therefore, TBs were identified as a crucial indicator of optimal fermentation. Moreover, redundancy analysis indicated that the tea pile's central temperature, moisture content, and pH were essential fermentation parameters ( P < 0.05). These findings deepen our understanding of MT_RPT flavor development mechanisms and provide valuable insights into precise fermentation control.
研究领域:
食品科学
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微生物学
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代谢组学
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DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
·
2017
·
IF 2.603
Ran Zhao,Dong Chen,Hualing Wu
To evaluate effects of Pu-erh ripened tea in hyperuricemic mice, a mouse hyperuricemia model was developed by oral administration of potassium oxonate for 7 d. Serum metabolomics, based on gas chromatography–mass spectrometry, was used to generate metabolic profiles from normal control, hyperuricemic and allopurinol-treated hyperuricemic mice, as well as hyperuricemic mice given Pu-erh ripened tea at three doses. Pu-erh ripened tea significantly lowered serum uric acid levels. Twelve potential biomarkers associated with hyperuricemia were identified. Pu-erh ripened tea and allopurinol differed in their metabolic effects in the hyperuricemic mice. Levels of glutamic acid, indolelactate, L-allothreonine, nicotinoylglycine, isoleucine, l -cysteine and glycocyamine, all involved in amino acid metabolism, were significantly changed in hyperuricemic mice treated Pu-erh ripened tea. Thus, modulating amino acid metabolism might be the primary mechanism of anti-hyperuricemia by Pu-erh ripened tea.
研究领域:
药理学
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代谢研究
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）