In this study, widely targeted metabolomics and chemometrics were utilized to comprehensively analyse the formation of taste compounds in Longjing green tea. A total of 580 non-volatile metabolites were identified by using ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry, and alterations in three metabolic pathways were investigated. Notably, the fixation process reduced phosphatidic acid levels, resulting in the formation of lyso-phosphatidylcholine and lyso-phosphatidylethanolamine, as well as the release of esterified polyunsaturated fatty acids. Baiye No.1 had high levels of L-glutamic acid and l-glutamine, while Longjing 43 showed elevated levels of flavones. Correlation analysis and sensory verification indicated that the specific concentration of L-leucine could decrease the umami of the tea. These findings advance our understanding of Longjing green tea quality improvement and cultivar development.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.foodchem.2024.139373 | DOI Listing |
Foods
August 2024
Hangzhou Tea Research Institute, CHINA COOP, Hangzhou 310016, China.
Premium green tea is a high-value agricultural product significantly influenced by its geographical origin, making it susceptible to food fraud. This study utilized nuclear magnetic resonance (NMR) spectroscopy to perform chemical fingerprint analysis on 78 Longjing tea (LJT) samples from both protected designation of origin (PDO) regions (Zhejiang) and non-PDO regions (Sichuan, Guangxi, and Guizhou) in China. Unsupervised algorithms and heatmaps were employed for the visual analysis of the data from PDO and non-PDO teas while exploring the feasibility of linear and nonlinear machine-learning algorithms in discriminating the origin of LJT.
View Article and Find Full Text PDFJ Sci Food Agric
January 2025
National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops, Tea Science Department of College of Horticulture and Forestry Sciences of Huazhong Agricultural University, Wuhan, China.
Background: Enshi Yulu tea (ESYL) is the most representative of steamed green tea in China, but its aroma formation in processing is unclear. Thus, the ESYL volatiles during the whole industrial processing were investigated using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry.
Results: A total of 134 volatiles were identified.
Food Res Int
October 2024
Tea Research Institute Chinese Academy of Agricultural Sciences, Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs, 9 South Meiling Road, Hangzhou 310008, China. Electronic address:
The flavor stability of tea beverages during storage has long been a concern. The study aimed to explore the flavor stability of Longjing green tea beverage using accelerated heat treatment trials, addressing the shortage of lengthy storage trials. Sensory evaluations revealed changes in bitterness, umami, overall harmonization, astringency, and ripeness as treatment duration increased.
View Article and Find Full Text PDFFood Res Int
July 2024
Key Laboratory of Tea Biology and Resource Utilization of Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China. Electronic address:
Variations in cultivars and cultivation altitudes have significant impacts on tea flavour compounds however lack of comprehensive understanding. This study provided insights into differential accumulation of crucial flavour compounds in response to cultivars, cultivation altitudes, and processing. Twelve flavonoids (262.
View Article and Find Full Text PDFFood Chem
September 2024
Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China. Electronic address:
Umami taste is a key criteria of green tea quality evaluation. The aim of this study was to comprehensively explore the key umami taste contributors in Longjing tea. The taste and molecular profiles of 36 Longjing green tea infusions were characterized by sensory quantitative descriptive analysis and LC-MS based metabolomics, respectively.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!