While the leaves wilt naturally, enzymes begin to ferment them. Processors interrupt the fermentation by stirring the leaves in heated pans, then rolling and drying them. Certain varieties are better suited than others for a particular processing method. For example, the China leaf from China and Formosa produces the best oolongs. Scented and spiced teas are made from black tea.
Orange pekoe refers to the size of the tea leaf.
Processed tea leaves are sorted into sizes by passing them over screens with different size holes. The largest leaves are orange pekoe, pekoe, and pekoe souchong. In brewing, flavor and color come out of the larger leaves more slowly than out of the broken and fine grades. The broken grades, which make up about 80 percent of the total black tea crop, produce a stronger, darker tea. But no matter how the tea may be doctored, in the United States the odds are overwhelming that it starts out black.