Black tea is a type of tea that is more oxidized than green, oolong, and white teas. It is made from the leaves of the Camellia sinensis plant and is characterized by its strong, bold flavor and dark color. The tea leaves are first withered and then rolled or crushed to release their flavor compounds. The leaves are then allowed to oxidize, which turns them dark brown or black and gives them their distinctive flavor. The oxidation process is stopped by heating the leaves, either by steaming or pan-firing. Black tea is usually consumed with milk and sugar in many parts of the world, but can also be enjoyed plain.

Grading
The last process of making black tea involves grading, where the tea leaves are separated based on their particle size using sieves and cleaned by removing the dust. In China, black tea is graded from No. 1 to No. 6, which reflects the price. However, in other countries, grading only indicates the size and shape of the tea leaves and not their quality or price. The grading standards vary depending on the country, and there is no universal standard.
Processing Methods
There are two main methods of processing black tea: traditional and CTC (cut, tear, curl). The traditional method produces whole or loose leaf types, while the CTC method produces broken, fine, and dust types. The CTC method involves cutting and shaping the tea leaves simultaneously, making them easily extractable. After brewing, CTC method tea has a clear color and strong aroma, making them popular for making tea bags. Currently, approximately 60% of total black tea production is from the CTC method.
Types of Black Tea
Whole Leaf or Loose Leaf (without chipping)
OP (orange pekoe): Large leaf, carefully rubbed and twisted, and includes tips. The length of each leaf is 7-11mm. Most Darjeeling tea is of the OP type.
P (pekoe): Similar to OP, but without tips.
Broken Type
BOP (broken orange pekoe): Same leaves as OP but cut into 2-4 mm and includes more tips. The color and aroma are strong, making it the most popular kind.
BOPF (broken orange pekoe fannings): Smaller than BOP, about 1-2mm. Often used for tea bags.
D (dust): Powdery tea made with the CTC method.
Additional Information
T (tippy), G (golden), or F (flowery) are sometimes added in front of the above names to provide additional information about the leaves. However, there is no single criterion for these signs, and they are added as a complement to the tea. While some people prefer the taste of the orthodox method of processing, the CTC method has gained popularity due to its ease of extraction and strong aroma.