The Hunt for Wild Harvest Raw Pu’erh & What Exactly Is It?

We’re honored to introduce our new award-winning Wild Harvest Green Pu’erh. The process of hunting down this tea involved a great deal of hard work and an equally great deal of good luck. The hard work came in the form of navigating through rural tea farming regions of Yunnan, China, assessing tea farms for the quality of their tea trees and the adequacy of their production operations. This work relied heavily on the advice and expertise in cultivation practices of my professor, mentor, and dear friend, Dr. Zhang.

Foraging For Pu’erh

Finding premium wild harvest tea trees to create this tea meant visiting multiple Yunnan tea farming regions and asking the essential questions involved in tea procurement:

• What is the current health status of the leaves, branches, and roots of the tea trees in this area?
• How old are the trees?
• How have they been cared for over the last 20, 30, 40 years?
• How has the land been treated?
• How well equipped are the processing facilities in terms of both skill and equipment?

Providing answers to these questions requires a skill set that is not easy to acquire, but luckily, we had experts on our team (Dr. Zhang is also the luck part).  His expertise in tea tree cultivation stems from a bachelor’s, master’s and Ph.D. in Tea Science, in addition to a lifetime of work processing tea alongside tea farmers, and conducting research on various aspects of tea-related biochemistry. So, what did he teach us to guide our search for Wild Harvest Green Pu’erh?

Firstly, the quality of the tea we drink derives heavily from the growth conditions and environmental factors surrounding the tea plant [1,2,3,4]. Ideal growing conditions for Yunnan tea cultivars include mountainous terrain, cool, shady, and humid air, and rich soil with strong plant diversity [8]. These conditions allow wild tea trees to accumulate and preserve high amounts of L-theanine [5], a compound that accounts for the naturally sweet and savory taste of premium tea [6,7], in addition to other compounds that contribute to rich flavor in tea leaves.

Navigating this type of terrain, however, is not easy. Yunnan is among the least developed Chinese provinces, and these mountain regions have few roads running through them. What that meant for our hunt to find wild harvest tea was a lot of off-road driving and a lot of bushwhacking. The Tea Spot founder, Maria Uspenski, and I spent a week in Yunnan traveling and bushwhacking with local farmers in search of wild tea trees. We called ourselves The Laowai Tea Hunters (Laowai is a friendly name for foreign people).

Our local guides were Hani minority people who were highly proficient in using machetes to cut paths through the dense forest. In some areas the slope got steep, and their machetes would second as a whittle, fashioning nearby branches into flawless walking sticks to help us keep our balance (they, of course, never needed walking sticks). When thirsty, we drank water directly from the mountain streams. The refreshing mountain spring water always served as a crisp reminder that we were in tea heaven.

When we finally found our wild harvest trees, I heard the words of Dr. Zhang ringing through my head, “find trees that are living, surviving, and thriving in outstanding condition.”

The thick trunks, deep roots, and vibrant green leaves were soft and tender to the touch. Even the young shoots coming off the branches tasted good to eat (Maria and I realized we have a thing for snacking on fresh tea leaves). Above us was a forest canopy that offered shade, allowing our tea trees to grow slow and steady, accumulating rich nutrients in every leaf. Slow tea tree growth leads to more accumulation of savory L-theanine, aroma precursors (I’ll explain those later), and a rich variety of other tea compounds that add up to bigger, bolder flavor in your teacup [9]. To finally find our long-sought wild harvest trees meant that every step of the journey, every mile trudged and every bush… whacked… was absolutely worth it.   So you see what we mean by the first two words in the name “Wild Harvest Green Pu’erh” but what about the second two?

Defining A Green Pu’erh

Without dipping too deep into the wild world of pu’erh tea, let’s talk briefly about what defines a green pu’erh, and what its special processing techniques are.  First, let’s establish that there are two main types of Yunnan Pu’erh; the dark one, and the green one. The dark one, also called shu, shou, cooked or ripe pu’erh, is fermented and has the classically dark liquor, chocolate aroma notes, and silky smooth mouthfeel that many of us commonly associate with pu’erh tea. It’s a lovely tea, I highly recommend it, but here we are talking about dark pu’erh’s cousin, green pu’erh.

I’ve come to view green pu’erh as something like an “aged green tea,” or perhaps better yet, a green tea that has been crafted in order to age with grace. In order to let green pu’erh age gracefully into a richer and developed tea over time, there are certain little ‘tweaks’ made to the original green tea production recipe. These processing tweaks were taught to our friends in Yunnan directly by Dr. Zhang himself.

The initial step in green tea production (called “kill-green”) is done at a lower temperature during green pu’erh production than during normal green tea production. Lower temperature kill-green serves the purpose of leaving some enzymes in the tea still active [10].

These enzymes serve to slowly make the tea less bitter and more sweet over time by oxidizing catechin compounds. This provides green pu’erh with a flavor profile that resembles normal green tea, but sort of feels more “mellowed out.” Normal green tea is heavy on the “green” aromas (grassy/vegetal), but green pu’erh leans to more “sweet green” aromas (honey/floral/honeyed tobacco).

As the aging continues over time, catechins continue to break down into even sweeter, richer, and more diverse sets of flavor compounds than what is normally found in green tea [11,12,13].  After around 3-5 years of aging, aromas notably take on woody and earthy attributes. These subtle changes are thanks to special green pu’erh production techniques, namely lower temperature kill-green… (the name “kill-green” actually comes from the idea that one is ‘killing’ the enzymes that would otherwise change the fresh leaf over time, had the enzymes not been killed. True kill-green, such as that in green tea, prevents the slow aging over time. But in green pu’erh we aim to not fully killing the enzymes, aka not fully kill the green. we are more just ‘injuring the green’… let’s call it the injure-green from now on.)   

Sun-Dried vs. Oven Dried Processing

Another small processing tweak that Dr. Zhang insists upon is a change in the drying process.

Normal green tea is oven-dried, but green pu’erh is sun-dried. Sun-drying is a specialty of Yunnan teas in particular because Yunnan is… really sunny. Sun-drying tea is technically feasible in other climates, but it’s riskier. You see, in order to sun-dry successfully, one needs a full day of strong, crisp sunshine. If clouds suddenly roll in the late afternoon before the tea is finished drying, it will affect aroma formation in the leaves and ultimately lower the overall quality of the tea, creating a musty smell. . Yunnan farmers are willing to roll the dice on sun-drying their tea because it is so consistently sunny in that region of China.

Sun-drying is a step that, just like injure-green, contributes to the shift in aroma profile from green/vegetal to more honey/floral/honeyed-tobacco. I mentioned before the term aroma precursors. These are units within the cells of the tea leaf that consist of an aroma compound (called an aroma volatile) attached to a glycoside (a sugar) [16]. Direct sunlight breaks these units apart, releasing the aroma volatile from the sugar, allowing that volatile to contribute to tea aroma [15]. What this means is that a sun-dried tea will contain aroma compounds that other teas simply cannot produce without UV rays from the sun to break down aroma precursors. With a trained palate, it’s possible to differentiate a sun-dried tea from an oven-dried tea by recognizing these unique aroma formation patterns. Pretty cool.

Additionally, sun-drying is a slower process than oven-drying, and allows enzymes to remain more active before the tea is fully dried. This extra drying time gives the catechins more opportunity to break down into sweeter and more mellow flavor compounds, even before the green pu’erh has started aging [16].

To briefly summarize, our Wild Harvest Green Pu’erh starts as a leaf deep in the mountains of Yunnan (in an area called the Wuliang mountains), then gets masterfully crafted using techniques taught by Dr. Zhang into honey-sweet delight that ages like fine wine.

This project has been a cumulative effort by Dr. Zhang, The Laowai Tea Hunters, The Tea Spot family, and many other individuals along the way that helped. We’ve rarely been so proud to add such a great new tea to our menu, and we can only hope that you enjoy drinking this treasure as much as we enjoyed the journey to find it. If you prefer the convenience of a pyramid tea bag, we’re also happy to accommodate with our premium raw pu’erh Wild Harvest in sachets.

As always, thank you for reading! Follow us on Instagram, or question/comment below :)

Resources

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[15] Jang, J. , Yang, Y. C. , Zhang, G. H. , Chen, H. , Lu, J. L. , & Du, Y. Y. , et al. (2010). Effect of ultra-violet b on release of volatiles in tea leaf. International Journal of Food Properties, 13(3), 608-617.

[16] Zhao, Y. , Chen, P. , Lin, L. , Harnly, J. M. , Yu, L. , & Li, Z. . (2011). Tentative identification, quantitation, and principal component analysis of green pu-erh, green, and white teas using uplc/dad/ms. Food Chemistry, 126(3), 1269-1277.