Oolong Tea

Definition

Oolong is partially oxidized tea, usually somewhere between 10 and 70 percent. The leaves are bruised by repeated shaking and tumbling so that oxidation starts along the torn edges, and the maker fires them at the moment the aroma peaks. That wide band makes oolong the most varied tea family: lightly oxidized Tieguanyin is floral and creamy, while heavily oxidized Dong Ding or Da Hong Pao turns toasty and dark-fruited.

Etymology

Oolong is a romanization of the Chinese 烏龍 (wūlóng), "black dragon." One common account credits a Fujian grower nicknamed Black Dragon; another points to the dark, twisted shape of the finished leaf.

In use

Used for semi-oxidized teas in the middle ground between green and black, especially when discussing Fujian and Taiwan styles or recommending a tea by roast level.

Oxidation, the Bruise and the Firing

Oolong production turns on three steps. First the leaf is withered in the sun and indoors to soften it and reduce moisture. Then it is bruised — traditionally by tossing the leaves in a bamboo drum or shaking them in a basket — so that the cell walls break along the edges. That damage exposes the leaf's enzymes to air and starts oxidation, which is why colour develops at the rim of the leaf while the centre stays green.

The maker stops oxidation at a chosen point by firing the leaf, usually with heat that denatures the enzymes. Deciding when to fire is the central skill of oolong making, because the leaf continues to change until the moment it is stopped. Firing slightly early preserves a greener, more floral tea; firing later allows the fruitier, riper notes to develop. The firing itself is then repeated or extended to dry the leaf and, in roasted styles, to add toast.

The result of this control is the widest range in tea. An oolong can be as green and floral as a high-mountain Tieguanyin at around 15 percent oxidation, or as dark and toasty as a heavily roasted Da Hong Pao at 60 percent or more. Both are oolong, and a drinker who dislikes one may well love the other.

The Main Families

Fujian oolongs include the Anxi style, where Tieguanyin is the best-known name, and the Wuyi rock teas such as Da Hong Pao and Rou Gui, which are grown on mineral-rich cliff soils and are typically roasted. Wuyi teas are often described as having yan yun, a rocky rhyme or mineral depth, which is a characteristic the region's producers work to preserve.

Taiwanese oolongs are generally lighter and higher-grown. Baozhong is the least oxidized and most floral; Dong Ding is medium-oxidized, roasted and often toasty; high-mountain oolongs from Alishan and Lishan are lightly oxidized, creamy and clean; and Oriental Beauty is an unusual heavily oxidized style made from leaf that has been bitten by a small leafhopper, which triggers a honeyed flavour.

Guangdong's Dan Cong oolongs are famous for their aromatic intensity and are often named after the fruit or flower they resemble — mi lan xiang (honey orchid), ya shi xiang (duck shit, a name with a folk origin), and others. Each producing area has its own vocabulary of local cultivars and styles, and the same cultivar grown in two regions can taste quite different.

How to Brew Oolong

Oolong is the tea most often brewed gongfu-style, and for good reason: it tolerates multiple infusions and changes noticeably across them. A typical approach is 5 to 8 grams of leaf in a 100 to 150 millilitre vessel, starting with a rinse and then infusions of ten to thirty seconds, lengthening as the session proceeds. Lightly oxidized oolongs generally want cooler water, heavier roasted ones water closer to boiling.

If you are brewing in a mug or a Western-style pot, use far less leaf — roughly 3 to 5 grams per 200 to 250 millilitres — and steep for two to three minutes for the first cup. Oolong generally forgives a longer steep better than green tea does, because its oxidized compounds are less aggressively astringent, but it will still turn bitter if left too long.

Water quality matters. Oolong's aromatics are the point of the tea, and heavily chlorinated or very soft water will mute them. Filtered water with a moderate mineral content is a common choice, and many drinkers find that roasted oolongs in particular taste fuller with slightly mineral-rich water.

Roast, Age and Storage

Roast level is a major axis independent of oxidation. A tea can be lightly oxidized and lightly roasted, which reads floral and fresh, or lightly oxidized and heavily roasted, which reads toasty and caramelised. Charcoal roasting is traditional for Wuyi teas and is often done in stages over weeks or months, with rest periods between, because the leaf needs time to settle after each firing.

Freshness expectations differ by style. Green-style oolongs are usually best within a year, and many drinkers keep them in the refrigerator. Roasted oolongs improve for a few months after roasting as the fire recedes, and can hold well for a year or more. Heavily roasted and deliberately aged oolongs, including some pu'er-style aged oolongs, are a separate tradition in which storage is part of the craft.

Store oolong airtight, away from light, heat and strong smells. If your oolong tastes flat and dull rather than merely light, the usual cause is age or poor storage rather than a bad tea. Giving a roasted oolong a few weeks to rest after opening, or re-roasting it briefly if you have the equipment and skill, can revive it somewhat.

Choosing and Enjoying It

The most useful question when buying is not which oolong is best but where you sit on the axis. If you like floral, creamy, delicate teas, look for high-mountain Taiwanese oolongs or Anxi Tieguanyin. If you like dark, toasty, structured teas, look at Wuyi rock teas and heavily roasted Dong Ding. If you like fruit and honey, Dan Cong and Oriental Beauty are the places to start.

Vintage and provenance markers in oolong are less standardised than in wine, but a few are meaningful: the region, the cultivar, the harvest season, the oxidation and roast levels, and increasingly the maker's name. Terms like competition grade refer to specific competitions with published criteria and are checkable; terms like premium are not.

Finally, oolong rewards attention more than almost any other tea. Because it survives many infusions, a single session can last an hour and show you a dozen different expressions of the same leaf. That is the pleasure of it, and it is also why oolong is the tea most often served at length in a specialty tea shop.