History of Oolong Tea

Sometime around the beginning of the Qing Dynasty (1644) a new style of partially oxidized tea sprung from the Wu Yi Mountains in China. When first mentioned in writing these teas were referred to as Rock Tea (Yan Cha) – a reference to their birthplace, the rocky soil of Wu Yi Shan, and a name that is still used for teas from this region today. These first teas soon came to be called Min Bei Wulong Cha, translated as “Northern Fujian Black Dragon Tea.”  In English, we use a short anglicized pronunciation of this title – “Oolong.”

The skill of making this special type of tea spread from the North of Fujian province southward to the Anxi and Guangdong provinces (Phoenix Mountain) before crossing the strait to Taiwan around 1810. These areas continue to be the four major categories of oolong tea: Wu Yi Mountain Rock Oolong, Anxi Oolong, Guangdong Dan Cong, and Taiwan Oolong.

The History of Oolong Tea

If you’ve read up on the histories of black tea and white tea, you’re likely to be well acquainted with China’s Fujian province.  This Southeastern coastal province, historically rich with ethnic diversity, has been a watershed of tea culture innovations for over a thousand years. In light of this history, it may come as no surprise that Fujian is responsible for creating and perfecting the first oolong teas. With biological diversity atop mineral-rich soil from weathered rock, Fujian’s Wu Yi Shan has long been recognized as a very special place that is well suited to grow very special tea.

Even prior to when it bore the oolong style, Fujian’s northern Wu Yi Shan region had already seen a golden age of tea production starting in the Tang Dynasty (618-907 AD) and peaking in Song (960-1279). The compressed cakes of tea made in Wu Yi Shan during the late Song dynasty were ornate treasures of their day, produced with a skilled method that has yet to be recovered from history.

In 1392, the newly established Ming Dynasty (1368-1644) instated a sudden prohibition on Wu Yi Shan’s most famous product: compressed cakes of tea.  An attempt to break the long-standing corruption and excess the tea trade perpetuated, the Ming Dynasty’s ban on compressed tea inadvertently imposed a dark age on Fujian tea making. With their factories raided and equipment confiscated, tea production was effectively shut down for 150 years. Ironically, from this dark age, all of the region’s most famous innovations were born. In the tumult of adjusting tea-producing infrastructure to produce loose leaf tea,

Fujian’s tea makers (likely Buddhist monks operating in their temples) invented charcoal roasting techniques to dry their tea. The slow charcoal roasting coupled with the accidental oxidization of their tea defined the characteristic flavor of Wu Yi Shan’s oolongs that continue to be produced today. Exactly when the process began no one knows for sure, though the first mention of this tea comes from a poem written by a monk living in Wu Yi Shan during the late Ming and early Qing Dynasties. He refers to this tea as “Yan Cha” (lit. “Rock Tea”) a name still commonly associated with the Wu Yi Oolong style today.

Wu Yi’s technique for making partially oxidized and charcoal dried tea spread south into the now-famous producing areas of Anxi and Chaozhou and across the strait to Taiwan. Over time this skill was embellished into distinct regional styles defined by the local tea bush cultivars, local soil quality, and local culinary preferences. Initially, though, all of this new style of tea resembled the dark, long and slightly twisted appearance of Wu Yi oolong tea today.  The name “Oolong” or “Wu Long” meaning “Black Dragon”, is likely a reference to the tea leaves’ unique resemblance to the curling body of mythical Chinese dragons.

Harvesting and Making Oolong Tea

Chinese oolong (wulong) is considered the most complicated tea produced and requires great skill and experience to craft their enormous range of flavors, fragrances, and liquor colors. Like all other types of tea, the flavor of oolong is greatly influenced by how little or how much the leaves have oxidized.  Leaves in oolong tea can range in oxidation from 15%-75%; a split between green tea’s near lack of oxidation and black tea’s near total oxidation.

Even before the leaves reach the defining step of oxidation, the process of making oolong tea contrasts with other styles. To begin, oolong tea’s harvest time is comparably later than green, white or yellow tea. Even “Spring Oolong” tea is not picked until April or even May. The standard for picking is three or four fresh, open leaves. Buds are very rare, but occasionally show up in Taiwanese made oolong. After picking, a year’s crop of oolong tea may take about a month to process before it goes to market in July.

The later picking time is necessary so producers can score bigger leaves that are durable enough for processing and also rich in aromatic oils. These aromatic oils are the flavor precursors brought out by carefully controlled oxidation and multiple stages of moisture removal.

Processing is different in the four different regions of oolong manufacture but the basic process can be described as follows. After picking, fresh tea leaves are withered in the sun for a few hours. Once the leaves lose enough moisture to become pliable, they are taken indoors and placed in bamboo trays and agitated to start their slow oxidation process. As tea oxidizes, it continues to wither in the controlled temperature of the room. After the tea is suitably oxidized, it is exposed to very high heat, ceasing all enzymatic oxidation. This is usually done by quickly sending the tea though a long tumbler of the hot air which replicates pan-frying. After this step, the tea may be shaped. This is when Anxi and Taiwanese oolong leaves are rolled into their distinctive ball form. The finished tea is then roasted over charcoal to further remove moisture until it becomes a suitably dry and stable product.

It’s important to note that when processing tea, the tea masters don’t think in terms of drying; they think in terms of removing moisture. That may sound like the same thing, but in Chinese thinking, it is very different. The tea is never completely dried, and at different stages of production, when the percentage of moisture content is at a certain level, different processes will be used. The tea master determines a tea’s moisture level by look, touch, and especially by smell. The smell of the leaves is critical, and tea masters do everything they can to avoid catching a cold during the tea making season.

There are many variations in the techniques to making oolongs, but in terms of general characteristics, the Anxi and Taiwan teas are most closely related, and the Wu Yi and Dan Cong oolongs are at least somewhat similar, with the Dan Cong tea making techniques coming from Wu Yi Shan.  Anxi and Taiwan teas are rolled into balls, are lightly oxidized and tend to be lighter tasting with an aftertaste that is sometimes stronger then the immediate taste. Dan Cong and Wu Yi teas are commonly more oxidized, and their leaves are rolled lengthwise. The immediate taste can be quite strong, with a sweeter, lighter aftertaste. Of course, there are many examples of exceptions to these generalities, but it is safe to say that all oolongs are very complicated and sophisticated teas, with a large spectrum of tastes, aftertastes, and smells. Different oolongs are prepared to accentuate the natural character of the tea bush and their growing area. Perhaps the most complex meeting of a master’s skill and the terroir is still the original oolong tea from Wu Yi Mountain.

Shapes and flavors of regional oolong are far from consistent. Shifting market preferences may quite literally reshape an oolong tea. As recently as 1995, Anxi oolong was not curled as we know it today, but looked much more like the dark, open leaf Rock Oolong from Wu Yi Shan. In the first decade of this century, greener, lightly oxidized tea have come into popularity. What we are examining is the ascendancy of newly developed Taiwanese manufacturing techniques and a marked preference for tea that delivers highly floral aromatics. Even more recently, aged oolong tea has become popular. Perhaps this can be explained as a backlash against the highly aromatic and lightly oxidized oolongs, or perhaps because of a surge of interest in aging teas caused by the pu-erh market boom. Regardless of why, aging oolong tea is not a long-standing traditional practice of experts, but is rather a practice of rural Chinese who have kept aged oolong tea (not to mention white tea and black tea as well) for its medicinal cooling quality.

Recently, oolongs have become interesting to the West because of current research being done with obesity and weight loss, but oolong teas with heavier oxidation have been famous for hundreds of years for aiding digestion, curing headaches, and cleansing the system from excessive use of smoke and alcohol. Though promising research has been published, the weight-loss claims surrounding oolong tea have yet to be substantiated by a large body of western medical research. As with all tea, we suggest the health benefits are just icing on the cake; the experience of drinking these teas are what it’s all about.

Still, physiological comforts to drinking oolong can be quite blatant if one takes some tea (especially Dan Cong!) after a heavy meal. Soothing to the stomach, oolong tea is a great counter balance to rich or greasy food.

A famous culinary grease cutter in its own right, Rock Oolong tea also offers nutrients from the mineral rich soil of Wu Yi Shan, which is popularly believed to benefit joint health, to relieve muscle aches and are considerably popular in Japan as an aid to liver health.

On the other end of oolong’s spectrum of processing, the lightly oxidized teas Anxi and Taiwanese oolong is viewed by traditional Chinese medicine as beneficial to the respiratory system.

The best oolong tea never becomes bitter, no matter how long it is infused. It is true that some good Dan Cong oolongs can have some bitterness that is sought after, especially by locals, but the better Dan Cong oolongs are sweeter and more smooth. A rich flavor through multiple infusions and a long aftertaste should be expected from all oolong teas.

Chas Kroll ∞ Tea Master