Widely targeted metabolomics analysis reveals the formation of nonvolatile flavor qualities during oolong tea manufacturing: a case study of Jinguanyin

Qingcai Hu; Yucheng Zheng; Yun Yang; Zi-Xin Ni; Bin Chen; Zongjie Wu; Huiqing Huang; Qingyang Wu; Zi-Wei Zhou; Shuilian Gao; Zhongxiong Lai; Hongzheng Lin; Yun Sun

doi:10.3389/fnut.2023.1283960

Widely targeted metabolomics analysis reveals the formation of nonvolatile flavor qualities during oolong tea manufacturing: a case study of Jinguanyin

Front Nutr. 2023 Dec 14:10:1283960. doi: 10.3389/fnut.2023.1283960. eCollection 2023.

Authors

Qingcai Hu^#^{1

2}, Yucheng Zheng^#³, Yun Yang^{1

2}, Zi-Xin Ni^{1

2}, Bin Chen¹, Zongjie Wu¹, Huiqing Huang^{1

2}, Qingyang Wu^{1

2}, Zi-Wei Zhou⁴, Shuilian Gao⁵, Zhongxiong Lai², Hongzheng Lin¹, Yun Sun¹

Affiliations

¹ Key Laboratory of Tea Science, College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, China.
² Institute of Horticultural Biotechnology, Fujian Agriculture and Forestry University, Fuzhou, China.
³ College of Tea and Food Science, Wuyi University, Nanping, China.
⁴ College of Life Science, Ningde Normal University, Ningde, China.
⁵ Anxi College of Tea Science, Fujian Agriculture and Forestry University, Quanzhou, China.

^# Contributed equally.

Abstract

Background: The manufacturing processes of oolong tea significantly impact its nonvolatile components, leading to the emergence of distinct flavor attributes. Understanding the dynamic changes in nonvolatile components during the manufacturing stages of the Jinguanyin (JGY) cultivar is crucial for unraveling the potential mechanism behind flavor formation.

Methods: Comprehensive metabolomics and sensomics analyses were conducted to investigate the dynamic changes in nonvolatile components throughout various phases of oolong tea processing, focusing on the JGY cultivar.

Results: A total of 1,005 nonvolatile metabolites were detected, with 562 recognized as significant differential metabolites during various phases of oolong tea processing. Notably, the third turning-over, third setting, and high-temperature treatments exhibited the most significant effects on the nonvolatile metabolites of oolong tea. JGY finished tea demonstrated a characteristic flavor profile, marked by mellowness, sweetness in aftertaste, and a significant Yin rhyme. This flavor profile was collectively promoted by the accumulation of amino acids and organic acids, the decrease in flavonols (3-O-glycosides) and sugar substances, the alteration of phenolic acids, and the stabilization of caffeine.

Conclusion: This study contribute to the understanding of the formation of oolong tea flavor qualities. The dynamic changes observed in various types of nonvolatile compounds during oolong tea processing shed light on the intricate interplay of metabolites and their influence on the final flavor characteristics.

Keywords: Jinguanyin; nonvolatile components; oolong tea; postharvest processing; tasting qualities; widely targeted metabolome.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by the China Agriculture Research System of MOF and MARA (CARS-19), the Major Special Project of Scientific and Technological Innovation on Anxi Tea (AX2021001), and Fujian Agriculture and Forestry University Construction Project for Technological Innovation and Service System of Tea Industry Chain (K1520005A06).