Time is short after the harvest. Several factors come into play to ensure that delicious beverage with your black tea.
The first step is "withering". Leaves are dried to remove 40-50% of the humidity and soften them to enable rolling, the second step in this delicate operation. Leaves are laid out on racks and ventilated before being rolled along their length to release essential oils. The strength of the tea taste will vary according to the intensity of the rolling process.
However, to obtain black tea the vital step is oxidation (sometimes known as "fermentation"). The leaves are stored at between 25° and 27°C for several hours. This is the operation that gives the tea leaf the dark colour we recognise.
Leaves are heated to nearly 90°C for twenty minutes to bring the oxidation process to an end, an operation known as "desiccation" or "torrefaction". The resulting leaves contain barely 5% water. This step is vital to ensure that tea retains its flavour and is well preserved. If there is too much water in the leaves afterwards, the tea can rot. Alternatively, if the humidity content is too low, the tea will lose some of its flavour. Even today, only human expertise can determine the right moment to end the fermentation and desiccation processes.
At this point, leaves can be whole or broken and can vary in length. The next step is ‘sifting’. Leaves are separated using sieves and are classified by "grade":
These teas infuse more rapidly and result in a stronger brew. Leaves broken at the end of the production process are called Dust or Fannings (if slightly larger). They are never altered and retain all the aromatic properties of the plantation where they were grown.