Many tea lovers have one question about the origin of Wuyi oolong’s “rock essence and floral aroma”, or Yanyun (Chinese: 岩韵, meaning: the elegance of the rocks). Is it the exquisite tea-making techniques or the unique geologic factors that make Wuyi oolong unique? Many people assume that it’s the tea-making that makes Wuyi oolong unique. However, if they’re right, we can produce Wuyi oolong everywhere if we apply the same tea-making in anther region. Is this true?
The answer is NO. For decades, tea makers all over the place have been trying to produce Wuyi oolong outside the Wuyi mountains area, but they all ended up failing.
One question arose from all these failures is that how come green tea such as the famous West Lake Dragon Well can be produced in various areas, but not Wuyi oolong? The primary reason is the fermentation. As we know, oolong is a half-fermented tea. As long as there’s fermentation, there’d be the involvement and the participation of microorganisms. Different regions have different microorganisms. This is why despite microorganisms in other tea-producing regions also engage in the fermentation process, they can never produce a fermentation similar to that of the Wuyi mountains.
In our last blog, we explained that the Wuyi mountains area has a unique landform called Danxia Landform. Because of the Danxia Landform, tea plants in the Wuyi mountains have a remarkable growing environment: cliffs. These cliffs provide crucial habitat for microorganisms that are native to the Wuyi mountains. When people say “place of origin”, it includes a specific set of microorganisms as well.
The common conclusion of the uniqueness of Wuyi oolong often involves 4 parts: the exceptional ecological environment and climate; abundant tea plant varieties; exquisite tea-making techniques; and finally, the exclusive microorganisms.
In fact, the term “half-fermented” is biological, and it’s closely associated with microorganisms. The reason we admire ancient tea makers is that they used their experiences and figured out an efficient “path” to involve microorganisms in tea-making long before the existence of modern biotechnology. The “path” here means the interwoven result of endogenous enzymes and exogenous enzymes.
The tea-making of Wuyi oolong is a great example to show how endogenous and exogenous enzymes work together in the process (see our previous blogs about oolong here). The “withering” and the “shaking” processes actually “activate” endogenous enzymes. The “red edge, green leaf” and the “grassy” fragrance is the work of endogenous enzymes.
After the “hot fixation” process, endogenous enzymes’ job is officially over. The fermentation of the next step relies on exogenous enzymes. The rolling process and the roasting process open up the gate for exogenous enzymes, which is the founder of Wuyi oolong’s “rock essence and floral aroma”.
Exogenous enzymes are not produce by tea plants. As its name suggests, exogenous enzymes come from microorganisms in the nature. These microorganisms include moulds, bacterias, and yeasts. All of them share one character which territorial.
During the rolling process, the integrity of the leaves is breached. Local (territorial) microorganisms take the opportunity and swoop into the process. Using the sugar in leaves as nutrients, microorganisms reproduce, spread and create a large amount of exogenous enzymes. Moulds play a major role during this process.
When the tea-making gets to the roasting process, moulds leave the stage because of the intense heat. Bacterias and yeasts start to show their significance.
Bacterias have a great adhesiveness and coercion, and they can erode “rocks” and “incise” rocks into nano-sized “particles”. The richness we taste from a Wuyi oolong is the mark of rocks. The rock essence is completed by bacterias including thermophiles and lactobacillus.
Yeasts, more specifically wild yeasts, are microorganisms live on the surface of the soil. Yeasts have an amazing capability of absorbing floral fragrances nearby then process them into a floral compound during the fermentation process. Finally, the heat from the roasting breaks down proteins and release the “floral aroma”.
In conclusion, “rock essence and floral aroma” is the work of microorganisms. It starts with endogenous enzymes, and it’s finalized and crafted by exogenous enzymes. Because of the existence of territorial microorganisms, we can only produce Wuyi oolong in the Wuyi mountains area.
We hope you enjoyed today’s blog. As always, if you have questions or suggestions, please leave a comment, tweet us @valleybrooktea or email the author directly at zhang@valleybrooktea.com. Please also follow us on Instagram @valleybrooktea and join our mail list to get our daily tea updates and our latest promotions!
*This is blog is inspire by a research on Man and the Biosphere Magazine publish by The Chinese National Committee for Man and the Biosphere. For more information about the publication (in Chinese), please contact us at zhang@valleybrooktea.com