Black

Black tea represents approximately 90% of the tea consumed in the Western world. It sets itself apart from green teas through a different processing method. The leaves are first exposed to hot air for several hours in order to reduce their water content to 50-60%. This step starts to free up the enzymes responsible for oxidizing the leaf. It also softens the leaves, which prepares them to undergo subsequent operations without breaking.

Next, the leaves are rolled (by hand or mechanically), allowing the essential oils to spread and to impregnate the buds. The aroma of the tea depends on these essential oils. A screen is used to sort the tea afterwards. The smallest leaves go directly to the next stage, while the larger, tougher ones undergo a second rolling.

Oxidation entails the chemical reaction of the leaves and their components (polyphenols) with air, humidity, and heat. Finally, comes firing. Drying the leaves in the oven stops the oxidation process.