Revealing the roles of solar withering and shaking processes on oolong tea manufacturing from transcriptome and volatile profile analysis
Journal
Food Research International
Journal Volume
201
Start Page
115586
ISSN
0963-9969
Date Issued
2025-02
Author(s)
Abstract
Solar and indoor withering in the manufacturing process of semi-fermented oolong tea are crucial for aroma formation. While the processes have been established through accumulated experience, the underlying mechanisms remain largely unknown. This study identified pairs of gene and volatile organic compound (VOC) that were significantly correlated and up-regulated during solar withering and the first shaking, including lipoxygenase 8 (LOX8) with 3-hexenyl iso-butyrate, terpene synthase 2 (TPS2) with β-ocimene and linalool, as well as tryptophan synthase β-subunit 2 (TSB2) with indole. Besides, two β-glucosidases (β-GH), β-GH1_1 and β-GH3_1, were up-regulated by more than 30-fold in these stages. When comparing the three manufacturing procedures, indole, nerolidol, β-ocimene, benzyl nitrile, and jasmine lactone, were largely accumulated only in the normal process, where both solar withering and shaking were included. These findings provide insights into the regulation of VOC accumulation under stresses during withering, and highlight the importance of specific manufacturing processes in the formation of oolong tea characteristic aroma.
Publisher
Elsevier BV
Type
journal article