College of Food Science, Sichuan Agricultural University, Yaan 625014, China.
College of Food Science, Sichuan Agricultural University, Yaan 625014, China.
Food Chem. 2024 Jan 1;430:136932. doi: 10.1016/j.foodchem.2023.136932. Epub 2023 Jul 26.
Microbial fermentation, a key step in Tibetan tea production, plays a pivotal role in forming the tea's unique quality. In our study, we mapped out the landscapes of major components, metabolomic signatures, and microbial features of Tibetan tea using component content determination, untargeted metabolomic analysis, and ITS and 16S rRNA sequencing. The results reveal that theabrownin content demonstrated a consistent growth trend post-fermentation, increasing from 41.96 ± 1.64 mg/g to 68.75 ± 2.58 mg/g. However, the content of epigallocatechin gallate (EGCG) significantly dwindled from 80.02 ± 0.51 mg/g to 8.12 ± 0.07 mg/g. Additionally, 518 metabolites were pinpointed as pivotal to the metabolic variation induced by microbial fermentation. The microbiome analysis exhibited a considerable shift in the microbiota signature, with Aspergillus emerging as the dominant microorganism. To conclude, these findings offer novel perspectives for enhancing the quality of Tibetan tea and abbreviating fermentation time through the regulation of microbiota structure.
微生物发酵是藏茶生产的关键步骤，对形成茶叶独特的品质起着关键作用。在我们的研究中，我们使用成分含量测定、非靶向代谢组学分析以及 ITS 和 16S rRNA 测序，描绘了藏茶主要成分、代谢组学特征和微生物特征的图谱。结果表明，发酵后茶褐素含量呈持续增长趋势，从 41.96±1.64mg/g 增加到 68.75±2.58mg/g。然而，表没食子儿茶素没食子酸酯（EGCG）的含量却从 80.02±0.51mg/g 显著减少到 8.12±0.07mg/g。此外，确定了 518 种代谢物是微生物发酵引起代谢变化的关键。微生物组分析显示，微生物群落的特征发生了很大的变化，曲霉属成为优势微生物。总之，这些发现为通过调节微生物结构来提高藏茶的品质和缩短发酵时间提供了新的视角。
