FOOD RESEARCH INTERNATIONAL
·
2023
·
IF 8.1
Rong-Jian Dong,Xie-Huang Sheng,Qian-Tu Xie,Xiaolin Huang,Fujie Yan,Songbai Liu
Yellow tea, a unique type of tea in China which is characterized with yellow color, has gained increasing popularity due to its pleasant taste. However, transformation of aroma compounds during sealed yellowing has been poorly understood. Results of sensory evaluation exhibited that yellowing time was the key factor for flavor and fragrance formation. A total of 52 volatile components during sealed yellowing process of Pingyang yellow soup were further collected and analyzed. The results demonstrated that the sealed yellowing process significantly increased the ratio of alcohol and aldehyde compounds in the aroma volatiles of yellow tea, which were primarily composed of geraniol, linalool, phenylacetaldehyde, linalool oxide and cis -3-hexenol, and their proportion increased with the prolongation of sealed yellowing. Mechanistic speculation revealed that the sealed yellowing process promoted release of alcoholic aroma compounds from their glycoside precursors and enhanced Strecker and oxidative degradation. This study revealed the transformation mechanism of aroma profile during the sealed yellowing process, which would facilitate processing of yellow tea.
研究领域:
食品科学
·
植物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Qiuyan Liu,Wenjing Huang,Caiyan Sheng,Yida Wu,Mingxia Lu,Tiehan Li,Jixin Zhang,Yuming Wei,Yujie Wang,Jingming Ning
Large-leaf yellow tea (LYT) is processed from both leaves and stems, resulting in a distinctive rice crust–like aroma. Tea stems may contribute differently to the aroma of LYT than leaves. This study aimed to clarify the specific contribution of stems to LYT. The volatile compounds in different components of LYT were extracted and analyzed using a combination of headspace solid-phase microextraction and stir bar sorptive extraction coupled with gas chromatography-olfactory-mass spectrometry. The results revealed high concentrations of compounds with roasty attributes in stems such as 2-ethyl-3,5-dimethylpyrazine (OAV 153–208) and 2-ethyl-3,6-dimethylpyrazine (OAV 111–140). Aroma recombination and addition experiments confirmed that the roasty aroma provided by stems plays a pivotal role in the formation of the distinctive flavor of LYT. This study offers novel insights into the contribution of stems to the aroma of LYT, which can be used for processing and quality enhancement of roasted tea.
研究领域:
食品科学
·
茶叶加工学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2020
·
IF 6.513
Haisong Wang,Jinran Chen,Pengfei Ren,Yiwen Zhang,Stanley Omondi Onyango
In this study, the impact of ultrasound irradiation on the structural characteristics and antioxidant properties of yellow tea polysaccharides with different molecular weights (Mw) were investigated. Native yellow tea polysaccharide containing YTPS-3N, YTPS-5N and YTPS-7N were prepared through precipitation with ethanol at various concentrations of 30%, 50%, and 70%, respectively, and irradiated with high intensity ultrasound (20 kHz) for 55 min to yield yellow tea polysaccharide including YTPS-3U, YTPS-5U and YTPS-7U. The molecular weight (Mw) of YTPS-3N (from 37.7 to 15.1 kDa) and YTPS-5N (from 14.6 to 5.2 kDa) sharply decreased upon ultrasound irradiation, coincidentally particle size (Zavg) was also significantly reduced for YTPS-3N (40%), YTPS-5N (48%) and YTPS-7N (54%). The high-performance liquid chromatography and Fourier transform-infrared spectroscopy analysis revealed a partial degradation of native yellow tea polysaccharide treated with ultrasound, though the monosaccharide composition was not altered. Furthermore, changes in morphology and the breakdown of native yellow tea polysaccharide upon irradiation was confirmed with the circular dichroism spectrum, atomic force and scanning electron microscopy. As a consequence, irradiation of yellow tea polysaccharide increased free radical scavenging activity with YTPS-7U exhibiting the highest levels of 2, 2-diphenyl-1-picrylhydrazyl free radical, superoxide and hydroxyl radicals scavenging activity. These results suggest that the alteration of the spatial structure of yellow tea polysaccharide can enhance its antioxidant activity which is an important property for functional foods or medicines.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Yifan Li,Jixin Zhang,Huiyan Jia,Yue Pan,Yong-Quan Xu,Yujie Wang,Wei-Wei Deng
Roasting is essential for processing large-leaf yellow tea (LYT). However, the effect of the roasting on the metabolic and sensory profiles of LYT remains unknown. Herein, the metabolomics and sensory quality of LYT at five roasting degrees were evaluated by liquid/gas chromatography mass spectrometry and quantitative descriptive analysis. A higher degree of roasting resulted in a significantly stronger crispy rice, fried rice, and smoky-burnt aroma ( p < 0.05), which is closely associated with heterocyclic compound accumulation (concentrations: 6.47 ± 0.27 – 1065.00 ± 5.58 µg/g). Amino acids, catechins, flavonoid glycosides and N -ethyl-2-pyrrolidone-substituted flavan-3-ol varied with roasting degree. The enhancement of crispy-rice and burnt flavor coupled with the reduction of bitterness and astringency. Correlations analysis revealed the essential compounds responsible for roasting degree, including 2,3-diethyl-5-methylpyrazine, hexanal, isoleucine, N -ethyl-2-pyrrolidone-substituted flavan-3-ol (EPSF), and others. These findings provide a theoretical basis for improving the specific flavors of LYT.
研究领域:
食品科学
·
代谢组学
✓ 已验证
产品关联
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
·
茶叶化学
✓ 已验证
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
·
食品科学
·
茶叶加工学
✓ 已验证
产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2024
·
IF 6
Caiyan Sheng,Mingxia Lu,Qiuyan Liu,Huan Zhou,Zhichao Xiong,Tiehan Li,Yuming Wei,Jixin Zhang,Han Ke,Yida Wu,Yujie Wang,Jingming Ning
Roasting is a key process in the production of large-leaf yellow tea (LYT) and substantially affects the formation of its aroma. In order to investigate the effect of roasting method on the aroma of large-leaf yellow tea and to identify the potential causes. In this study, guided by molecular sensory science, the aroma components of charcoal-roasted, electric-roasted and drum-roasted LYTs were analyzed using headspace solid phase microextraction and solvent-assisted flavor evaporation in conjunction with gas chromatography-mass spectrometry, and the data were visualized and analyzed using SMICA, SPSS and Origin. The results of quantitative descriptive analysis revealed that rice crust, burnt, corn and floral aromas were significantly different between the three samples. The results of aroma extract dilution and odor activity value analyses revealed that 2,4,5-trimethyloxazole, 1-ethylpyrrole-2-carboxaldehyde, 2-ethyl-3,5-dimethylpyrazine, 3-ethyl-2,5-dimethylpyrazine, linalool, 2,3-diethyl-5-methylpyrazine, 3,5-diethyl-2-methylpyrazine, β -damascenone, and ( E )- β -ionone were the main compounds responsible for differences in the aroma of LYT subjected to different roasting methods. Aroma recombination and addition experiments verified these findings. All in all, charcoal roasting enhances the rice crust and burnt aromas of LYT, and drum roasting facilitates the presentation of floral and corn aromas. This study provides a theoretical basis for the processing of high-quality LYT.
研究领域:
食品科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Yuming Wei,Jixin Zhang,Tiehan Li,Mengjie Zhao,Zhenshuo Song,Yujie Wang,Jingming Ning
An optimized yellowing process for yellow tea (YT) was recently developed. The study found that the optimized yellowing process caused a significant increase in sweet and floral aromas by 31.3% and 24.0%, respectively. A total of 21 aroma-active compounds were identified using gas chromatography-mass spectrometry (GC–MS) and gas chromatography–olfactometry (GC-O) combined with sensomics analysis. Quantification of the 15 aroma-active compounds and calculation of odor activity values (OAVs) showed that the OAVs of sweet and floral aroma compounds increased significantly by 986.2% and 46.4%, respectively, after the optimized yellowing process. Sensory-directed aroma reconstitution and omission experiments confirmed that dimethyl sulfide, 3-methylbutanal, β -ionone, β -damascenone, geraniol, phenylacetaldehyde, and linalool were the key odorants in YT after the optimized yellowing process. Odorant addition tests further demonstrated that β -damascenone (OAV 590.4) was the main odorant for YT sweet aroma enhancement, while β -ionone (OAV 884.6) was the main odorant for YT floral aroma enhancement.
研究领域:
食品科学
·
茶叶加工学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Bioscience
·
2024
·
IF 4.8
Dianhui Wu,Ziqiang Chen,Yongxuan Lv,Lixia Yang,Hua Liu,Ran Qiu,Hengde Xu,Jianbo Li,Jian Lu,Guolin Cai
The utilization of mixed cultures of Saccharomyces and non -Saccharomyces cerevisiae strains to improve the quality and aroma complexity of wines has garnered considerable attention as of late. In this study, three non -S. cerevisiae strains exhibiting a strong β-glucosidase production capacity were screened from the yeasts preserved in the laboratory. Subsequently, the physiological characteristics of the strains were evaluated through growth curve analysis as well as alcohol and osmotic pressure tolerance experiments. Finally, the non -S. cerevisiae strain S14 ( Torulaspora delbrueckii ) was selected and applied to ferment Yuan'an yellow tea beer combined with S. cerevisiae S189. The results showed that the optimal fermentation performance was achieved when S14 was inoculated first, followed by the addition of S189 after 12 h of fermentation, with an S14:S189 ratio of 10:1. Mixed fermentation resulted in a significant increase in the concentration of volatile flavor compounds in beer, particularly terpenes, alcohols, esters, and acids, which exhibited levels of 520.98 μg/L, 5534.28 μg/L, and 1631.80 μg/L, respectively; these values were 299.25%, 32.45%, and 56.57% higher compared to purebred fermentation. Furthermore, mixed fermentation demonstrated an improvement in the antioxidant activity of beer, as evidenced by the increase in the comprehensive evaluation score (CES) from 1.86 to 2.89. Overall, these findings indicated the notable advantage of non -S. cerevisiae strain S14 in fermenting Yuan'an yellow tea beer.
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Shuai Dong,Yifan Zuo,Yongning Wei,Qianfeng Yang,Jingfei Shen,Kun Liu,Chuxuan Huang,Qianying Dai,Jingming Ning,Luqing Li
Aroma quality is a key indicator of the degree of roasting of large-leaf yellow tea (LYT). In this study, a colorimetric sensing array (CSA) composed of tetraphenylporphyrin (TPP) was designed for the rapid quantitative detection of key volatile organic compounds (VOCs) in LYT. First, the responses of the CSA system were compared under three environmental conditions. The response intensity of the TPPs to the VOCs was analysed using density functional theory (DFT). Finally, on the basis of the DFT calculations, a streamlined CSA sensor incorporating a least-squares support vector machine model was designed for the quantitative detection of 2-ethyl-3,5-dimethylpyridazine, 2,5-dimethylpyrazine, benzaldehyde, dihydro-2-methyl-3-furanone, linalool, and trans- β -ionone at levels ranging from 0.005 to 5 ppm. The predictive coefficients and relative predictive deviations of the quantitative model ranged from 0.82 to 0.93 and 1.75 to 2.65, respectively. This study provides a theoretical basis for the construction of CSA and a novel perspective on the monitoring of tea processing and quality.
研究领域:
食品科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Xiangyang Guo,Chi-Tang Ho,Wilfried Schwab,Chuankui Song,Xiaochun Wan
Large-leaf yellow tea (LYT) imparting unique toasty flavor is a traditional beverage in China. The volatile composition of LYT after full fire processing (FF-YT) was determined by different extraction methods. Steam distillation (SD), solid-phase microextraction (SPME) and headspace (HS) were applied for analysis of tea body notes, tea infusion and dry tea aroma, respectively. A total of 143 volatile compounds was identified by the three methods, of which SD-FF-YT, SPME-FF-YT, and HS-FF-YT extracts contained 100, 72, and 56 volatiles, respectively. Heterocyclics and aromatic compounds were the main volatile composition of LYT and might be contributors to its crispy-rice-like odor. l -Theanine was demonstrated to contribute to the formation of tea volatiles. N -Ethylacetamide, formed in the l -theanine only model thermal reaction, was probably involved in the LYT volatile formation. The current results provide new insight into l -theanine on aroma formation, although the detailed formation mechanism remains largely unknown.
研究领域:
食品科学
·
化学
·
茶叶科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2025
·
IF 8
Ziyi Shen,Simeng Zhou,Yaru Zhang,Yuan Zhang,Hongyan Wang,Daxiang Li,Yijun Wang,Zhongwen Xie,Huifang Ge
Large-leaf yellow tea protein-derived oligopeptides (TPP) contain a substantial number of antioxidant peptides that facilitate skin damage repair and may be employed to mitigate skin photoaging. However, the potential alleviating mechanism by which TPP alleviates skin photoaging damage remains insufficiently understood. This study investigated the in vitro antioxidant capacity and cell migration-promoting ability of TPP. Additionally, it utilized ultraviolet (UV)-exposed and intrinsically aged ICR mice, which exhibit signs of skin aging, to assess the effects of an 8-week oral TPP intervention. The findings indicate that TPP exhibits potent free radical scavenging properties, which mitigate oxidative damage in Raw264.7 cells and promote the migration of NIH/3 T3 cells. TPP intervention significantly ameliorates oxidative stress and skin inflammation symptoms in UV-induced skin photoaging damage by restoring the activity of endogenous antioxidant enzymes and suppressing the mRNA expression of pro-inflammatory cytokines, including IL-1β , IL-6 , and TNF-α ., as well as inhibiting the MAPK/AP-1/MMP9 signaling pathways. This study proposes that TPP is a viable plant protein-derived nutritional supplement for the prevention of UV-induced skin photoaging damage.
研究领域:
营养科学
·
皮肤科学
·
分子生物学
·
食品科学
·
药理学
✓ 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）