Morus alba 'Seedless Dashi' is an excellent variety with large leaves, which is very suitable for making tea. GABA is an important functional component in mulberry leaf tea, but its role and influence on flavor components and metabolism of mulberry leaf tea are still unclear. In this study, metabolomics methods were used to comprehensively analyze the differences between externally added GABA mulberry leaf tea and non-added GABA mulberry leaf tea. The results showed that GABA treatment significantly increased the total amount and diversity of volatile components of mulberry leaf tea (+38.95%), especially the addition of 6 new pyrazine compounds, which gave mulberry leaf tea nutty and caramel characteristics. Compared with ordinary mulberry tea, 73 different metabolites were screened (65 up-regulated and 8 down-regulated). It was found that GABA tea promotes the accumulation of functional components by regulating amino acid and lipid metabolism pathways. This study provided a theoretical basis for the quality optimization of GABA mulberry leaf tea and confirmed that GABA has the dual role of flavor-enhancing and functional components in mulberry leaf tea.
Mulberry leaf tea (MT) is a popular Chinese food with nutrition and medicinal functions. Solid-state fermentation withEurotium cristatumof MT (FMT) can improve their quality. Differences in chromaticity, taste properties, and flavor characteristics were analyzed to evaluate the improvements of the sensory quality of FMT. After fermentation, the color of the tea infusion changed. The E-tongue evaluation results showed a significant decrease in unpleasant taste properties such as sourness, bitterness, astringency, and aftertaste-bitterness, while umami and saltiness taste properties were enhanced post-fermentation. Aroma-active compounds in MT and FMT were identified and characterized. A total of 25 key aroma-active compounds were screened in MT, and 2-pentylfuran showed the highest relative odor activity value (ROAV). A total of 26 key aroma-active compounds were identified in FMT, and the newly formed compound 1-octen-3-one showed the highest ROAV, which contributed to FMT’s unique mushroom, herbal, and earthy flavor attributes. 1-octen-3-one, (E)-2-nonenal, trimethyl-pyrazine, 2-pentylfuran, and heptanal were screened as the potential markers that contributed to flavor differences between MT and FMT.E. cristatumfermentation significantly altered the sensory properties and flavor compounds of MT. This study provides valuable insights into the sensory qualities of MT and FMT, offering a theoretical basis for the development of FMT products.
危险品化学品经营许可证（带存储）