Since the previous steps are all about controlling the loss of water from the tea leaves, The next step - "waving" (浪菁) is about "retaining water". Waving also serves another important function for the tea leaves, which we will discuss briefly after we illustrate how "waving" is done.
Different from the "hand-made stirring" (Yes, we just invented that term), this "waving" process involves the assistance of a modern machine in order to make sure the vein of the tea leaves were all properly damaged. By "properly" we mean heavy enough to break the spongy tissue inside the tea leaf to allow the enzymes to escape and interact with the polyphenols, carbohydrates, and amino acids.
A certain amount of tea leaves have to be dropped into this bamboo roller machine that is mechanized with the flip of an electrical switch. The machine might seem dated, but it's very effective, and with a capacity that's quite perfect for this tea factory..
Old mechanism, but not dated.
Although it's called "waving," the bamboo rolling cylinder does not roll crazily like a "wave", but instead rotates very gently and slowly such that it seems to be barely moving at all!
As the cylinder rolls slowly the aroma of the tea leaves begins transforming from "un-ripe peach" to "un-ripe banana". This transformation of aroma would be very subtle to most of the people, but to the seasoned tea processing staff this transformation signal a step in the right direction!
Once the "waving" is done, the tea leaves would be released to the ground for the very next process. A process that is crucial to all oolong teas.
Some of the tea leaves must be removed by hand since they tend to get stuck inside even after the door has been opened and facing down. Special care must be taken to avoid bruising the leaves.
Now we enter the stage of "oxidation". In Mandarin, this stage is actually called "fermentation" but using it in tea processing is actually inaccurate, since fermentation refers to an environment which is lacking oxygen.
Oxidation is a very simple process, the tea leaves are loaded back onto the trays and wait for four to twelve hours. The duration of time depends on objective factors and how the "master" would like the tea to be.
With lighter oxidation, the flavor of the tea will taste similar to the classical Bao Zhong oolong - fresh and non-roasted. If taking a heavier approach, the master roasts it and rolls it more heavily, just like the traditional Dong Ding.
Nowadays, we combine these two approaches together to create the so called "jade oolong" - lighter oxidation than Dong Ding, but heavier rolling than Bao Zhong.
After oxidation has been completed (when "the master" says so), the tea leaves will now enter the crucial stage to stop the activity of enzymes. This stage is called "kill-green" 杀青.
Below: The tea is undergoing the "kill-green" process inside this fast rolling machine.
Of course, the term "kill-green" does not mean really killing the tea. By the application of heat and agitation the enzymes in the tea will reach stasis, thus halting the oxidation of the tea, bringing it to it's final "finished" stage.
During the "kill-green" process, lots of moisture will be released from the tea leaves, causing the room to be hot and humid even during the middle of the night. And again, controlling the water content level in the tea leaves is the key to this process. Although the main purpose of this "kill-green" stage is to release most of the moisture from the tea leaves by raising the temperature, which also halts the degenerative activity of the enzymes. The tricky part is there must be a small amount of moisture kept inside the tea leaves to not only prevent overly dry and brittle tea leaves, but also using that last bit of moisture to produce the temperature need that brings the enzyme activity to a full stop.
What will happen if too much moist is kept inside the tea leaves? Good question! If the tea leaves have too much moisture, the enzymes will be reactivated again, resulting an unstable and possibly spoiled final product.
Below: The room is very hot and humid now although it's already 2:00 AM!
Once the tea is considered done, the machine front of the machine will face down to drop the material out.
The teas will now enter the final part of processing. After this part is done, the tea could be called as "minced tea" (茶臊), which is a normal term to refer tea that just finished the "kill-green" phase.
This part is called "Rolling." As we mentioned previously, tea rolling has two styles ─ light rolling for Bao Zhong with light oxidation; heavy rolling for Dong Ding with heavier oxidation. As we said before, our "Tall Tree Oolong" (and any other kind of usual high mountain jade oolong), is a combination of both styles, it is not surprising that this combined style will be "heavy rolling" and "light oxidation". Such a process is still relatively new compared to the traditional Bao Zhong and Dong Ding style of processing.
Below: 3:00 AM, everybody is still up working on batches of tea. The picture showed below is a basic rolling machine.
Rolling serves two purposes - first purpose is obvious, to make it into a smaller volume for logistics and storage; the second purpose being less obvious, is to break the cell wall of the tea leaf thus allowing the material inside the tea leaf to dissolve into the hot water when it's brewed.
To make a half-rolled oolong like Dong Ding, the tea will normally go through another process called "mass rolling" (團揉) to make a ball-shape like tea, which requires a machine that is designed specifically for mass rolling. Unfortunately, the factory did not have such a machine, so the only way to achieve a heavy rolling was to extend the rolling duration using the normal rolling machine.
Below is an example of the "mass rolling" machine in another bigger tea factory.
After rolling, we could finally entered the very last stage of tea processing to make the so called "draft tea" (毛茶). This is also, possibly the top one tea processing "term" most tea lovers know. Some of our wise reader probably already know what we are about to discuss right now, exactly, we are going to enter the "roasting" part of tea processing.
Like what we saw back at the historical black tea site, the roasting will require a huge machine to make it efficient. As a result, our mini bamboo roaster will certainly not be applied here. What was used instead, was this huge machine called "Roasting Machine Type A" (full name in Chinese is 甲種乾燥機).
Time to get some tea roasted.....
One thing must be made clear here. The concept of "roasting" demonstrated here is still a little bit different from the more common form of "roasting". The roasting that happened here was accomplished for the purpose of making the tea "fully dried". When the tea is fully dried, it can be referred to as "draft tea". "Draft tea" (aka mao cha 毛茶) means the material has now reached a stable condition as is considered to be a final product. How to further craft the flavor and style of the tea through the commonly known "roasting" is a very different story. Every tea roasting "expert" will bear a set of roasting philosophy of their own, which is very different from the "roasting to stabilize the tea" that we are seeing here. Since after rolling, the moisture within the tea leaves must be dried out below a certain percentage to finalize the tea products for the tea merchant who will then carry the responsibility of conveying the tea to their customers.
At last, by 5:30 AM, the first batch of draft tea is finally complete! The tea itself documented this three part series is a lovely tea and is available here: "Organic Tall Tree Jade Oolong".