After tea leaves are harvested from the tea plant, all teas except non-fermented green tea must undergo a process called “withering.”
The main purposes of withering are:
- To soften the leaves, making them pliable for rolling
- To reduce moisture content, allowing catechins inside the leaves to oxidize properly and reach the desired fermentation level
Withering is generally classified into two types:
◆ Active Withering (also known as Natural Withering or “Water Run-Off”)
In this method, tea leaves lose moisture naturally through evaporation, either outdoors or indoors.
- 1. Outdoor Withering: Tea leaves are exposed to sunlight, where the heat helps evaporate surface moisture, remove grassy flavors, and soften the leaves. Once the desired softness and clarity of aroma are achieved, the leaves are brought indoors.
- 2. Indoor Withering: Leaves are spread indoors and allowed to release moisture slowly through the underside stomata and edges. Periodic turning of the leaves ensures even moisture evaporation, while also increasing the level of fermentation with each turn.
◆ Passive Withering (also known as Artificial Withering or “Moisture Reduction”)
This method uses machines or non-natural means such as dehumidifiers or hot air blowers to control the environment and force the tea leaves to lose moisture.
Regardless of the method, withering is one of the most labor-intensive and critical steps in tea processing. During this time, oxidation is already occurring, so farmers must constantly monitor and manage temperature and humidity to ensure stable, high-quality tea production.
