Tea has strong antibacterial power. Gargling with black tea can prevent colds caused by viral infection, prevent tooth decay and food poisoning, and reduce blood sugar and high blood pressure. Compared with fresh leaves, aroma substances increased significantly. Therefore, black tea has the characteristics of black tea, red soup, red leaves and sweet taste. Qimen black tea is the most famous black tea in China, which is the second largest tea in China. The export volume accounts for about 50% of the total tea production in China, and the customers are all over more than 60 countries and regions.