To produce black tea, the leaves are allowed to wilt after being picked. They are then rolled, breaking down the cell structures, allowing the cell sap to rise to the surface. Next, the fermentation phase begins: The cell sap bonds with the oxygen in the air, and the tea leaves turn copper in colour and develop their distinctive aroma. After being dried, the tea leaves are sorted according to the common tea leaf grades. View our range of black teas and black tea blends.