2. Academic Validation
  3. New insights into the influences of baking and storage on the nonvolatile compounds in oolong tea: A nontargeted and targeted metabolomics study

New insights into the influences of baking and storage on the nonvolatile compounds in oolong tea: A nontargeted and targeted metabolomics study

  • Food Chem. 2022 May 1:375:131872. doi: 10.1016/j.foodchem.2021.131872.
Jiakun Peng 1,  Weidong Dai 2,  Meiling Lu 3,  Yongquan Yan 4,  Yue Zhang 5,  Dan Chen 5,  Wenliang Wu 5,  Jianjian Gao 1,  Minghua Dong 4,  Zhi Lin 6
Affiliations

Affiliations

  • 1 Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, Zhejiang 310008, China; Graduate School of Chinese Academy of Agricultural Sciences, Beijing 100081, China.
  • 2 Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, Zhejiang 310008, China. Electronic address: [email protected].
  • 3 Agilent Technologies (China) Limited, Beijing 100102, China.
  • 4 Yongchun County Agricultural and Rural Bureau, Quanzhou, Fujian 362600, China.
  • 5 Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, Zhejiang 310008, China.
  • 6 Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, Zhejiang 310008, China. Electronic address: [email protected].
PMID: 34953237 DOI: 10.1016/j.foodchem.2021.131872
Abstract

A nontargeted and targeted metabolomics method was applied to comprehensively investigate the influences of baking and storage on chemical constituents in fresh-, strong-, and aged-scent types of Foshou oolong teas. The contents of N-ethyl-2-pyrrolidone-substituted Flavanols (EPSFs), flavone C-glycosides, gallic acid, and most lipids increased after baking and storage, while the contents of cis-flavanols, Alkaloids, flavonol O-glycosides, and most Amino acids decreased. Degradation, epimerization, and interaction with theanine were main pathways for the decrease in cis-flavanols. Approximately 20.7%, 12.8%, and 11.6% of epigallocatechin gallate were degraded, epimerized, and interacted with theanine after baking, respectively; 22.5% and 8.71% of epigallocatechin gallate were degraded and interacted with theanine after 10-year storage, respectively. Simulated reactions confirmed that the increases in EPSFs and apigenin C-glycosides were caused by interactions between theanine and Flavanols and between apigenin aglycone and glucose, respectively. This study offers novel insights into chemical changes during baking and storage of oolong tea.

Keywords

Baking; Flavone/flavonol glycosides; Metabolomics; Oolong tea; Storage.

Figures
Products