There are five stages in the tea's journey from the bush to your cup. They are Withering, Rolling, Oxidisation, Drying and Shifting. This post explains the first of those stages, Withering.
The point of withering is to extract part of the moisture from the freshly plucked leaf under controlled humidity conditions using a mixture of hot and ambient air. By the end of the process the leaf will have changed from a turgid leaf to one that is supple and pliable.
A Withering trough with freshly picked leaf
In years gone by the freshly plucked leaf would be placed on racks known as “tats” and left to naturally wither. Today however, withering occurs in a “withering trough”, but the aim remains the same. A trough is approximately 2m wide and 1m high and halfway up lies a mesh over which the leaf is spread. At one end is the fan that controls the airflow.
There are many factors that will determine how long or short the withering process should be including the recent weather conditions, especially if it has been wet, the quality of the green leaf, and how the leaf will be further processed.
Consistent withering is crucial. To achieve this the leaf will be turned occasionally to ensure that all the fresh green leaf is exposed to the humidity and air flow. In the end it is the experience of the withering supervisor who will determine when the leaf is ready. Through both touch and smell they will know when it can move to the next stage. They will take a handful of green leaf, roll it into a ball in the palm of their hand and if the leaves stay as a ball and there is a sap on the palms of their hand, then it indicates that the tea has been fully withered. An over withered leaf will be flaky and will lack flavour.
PMD University of Tea students getting a hands on lesson in the science of Withering
A withering supervisor is highly skilled and will be very experienced. They will be keeping a close eye on at least 24 troughs, ensuring that each has an even wither. There is no doubt that this part of the process involves science but also involves incredible skill.
As withering happens in the upper floors of a tea factory, the aroma created spreads widely to the local area and is unforgettable. Visits to New Vithanakande (NVK) estate illustrate this perfectly. Because the bungalows sit just above the withering sheds, visitors are greeted by the sweet caramel aroma that is found in NVK teas.
Next time we will be explaining the next stage of the process Rolling.