Preparation method of black tea

The invention belongs to the technical field of processing of tea leaves, and particularly discloses a preparation method of black tea. The preparation method of the black tea comprises the followingsteps of (1) performing withering: withering the tea leaves, performing rolling lightly, and performing illumination for withering; (2) performing rolling: performing four-grade rolling on the tea leaves by regulating the rolling pressure and rotating speed; (3) performing rolling post-treatment; (4) performing fermentation: performing circular fermentation and red light illumination on the tea leaves, and then performing ultraviolet illumination; (5) performing fermentation post-treatment; (6) performing drying; and (7) performing sieving. According to the preparation method of the black tea,the tea leaves are treated from various technologies, so that the appearance, the color and the fragrance of the tea leaves are effectively improved. The prepared tea leaves are high in sensory quality, high in nutrient value