Report from Engineering:
We’ve had the chief engineer and the bioengineer working on understanding the making of this tea. The bioengineer has just finished a project on tea leaves and their chemical properties, while the chief engineer was interested in the engineering process behind making different types of tea.
Tea leaves, when picked fresh from the plant, contain enzymes that cause oxidation. The amount of oxidation determines the type of tea that is produced – green, oolong, or black. Green tea is not oxidized, oolong tea is partially oxidized, and black tea is fully oxidized.
Once the leaves are picked, they are spread out to wither for a few hours. This removes some of the moisture from the leaves and makes them pliable. The leaves are then bruised to release the enzymes that cause oxidation. This can be done by rolling the leaves by hand or by using machines.
The chief engineer was particularly interested in the machine aspect of the process and asked how the machines work. The bioengineer explained that there are different types of machines that can be used, but they all essentially do the same thing – they bruise the leaves. Some machines use rotating drums, while others use blades that chop the leaves.
The next step in the process is oxidation. The leaves are spread out and left to oxidize for a period of time. The length of time depends on the desired type of tea. Green tea is not oxidized at all, oolong tea is oxidized for a short period of time, and black tea is oxidized for a longer period of time.
The chief engineer asked if there were any factors that could affect the oxidation process. Temperature, humidity, and the amount of oxygen in the air can all affect the oxidation process. It is important to control these factors to ensure that the tea is oxidized properly.
Finally, the leaves are fired or dried to stop the oxidation process. This is done by heating the leaves in an oven or on a hot surface. The amount of heat used and the length of time the leaves are heated can also affect the final flavor of the tea.
We are all impressed by the complexity of the process, especially considering how long ago (relatively speaking) these processes were developed and the amount of engineering involved in making different types of tea.