Method for preparing fermented tea, fermented tea and application of fermented tea

The invention provides a method for preparing fermented tea, the fermented tea and application of the fermented tea. The method comprises the following steps: mixing tea leaves with theanine, and then fermenting the tea leaves mixed with theanine by using aspergillus niger. According to the method disclosed by the invention, the fermented tea rich in N-alkyl-pyrrolidone substituted flavanol, especially the Pu'er tea extract 401 series compounds, can be produced, and the content of the Pu'er tea extract 401 series compounds can be at least more than 0.2%. Moreover, the fermentation condition is suitable for fermentation culture after adding theanine, the biggest advantages of the method disclosed by the invention can be exerted, and excellent sensory quality of the fermented tea is ensured while high content of Pu'er tea extract 401 series compounds is obtained. 本发明提供了制备发酵茶的方法、发酵茶及其应用。所述方法包括将茶叶与茶氨酸混合，然后利用黑曲霉对混合有茶氨酸的茶叶进行发酵。本发明的方法能够产生富含N-烷基-吡咯烷酮取代黄烷醇，特别是普洱茶素401系列化合物的发酵茶，其中普洱茶素401系列化合物的含量至少可大于2‰。而且，本发明的发酵条件适合添加茶氨