Response Surface Optimization of The Fermentation Process of Mulberry Leaf Tea by

\n1-Deoxynojirimycin (DNJ), a functional ingredient in mulberry leaf tea, was used as an indicator during the response surface optimization of the solid-state fermentation process to prepare mulberry leaf tea with Eurotium cristatum in order to improve the quality of the product. The product α-glucosidase inhibitory activity was then examined. The findings indicate that the optimal conditions for preparing mulberry leaf tea fermented by E. cristatum are a 40% moisture content in the substrate, a 5% inoculum amount for 6 days of fermentation, and a maximum DNJ content of 3.09 mg/g. The resulting products had a golden yellow color, a reddish-brown tea broth, a full-bodied taste, and no longer had any grassy flavor. These results effectively improved the quality of the mulberry leaf tea and offered a theoretical foundation for the production of high-quality mulberry leaf tea.\n