Oolong Tea

also called wulong, blue, blue-green, or semi-oxidized tea

While oolong is the most common way to refer to these teas in North America, it's sometimes also called wulong tea.  The name (from the Chinese ou-long) means "black dragon" and probably refers to its dark leaves that are often mixed with lighter colored leaves. 

It saddens me to hear people stereotype and dismiss all oolong teas because of a tepid experience they had with it years ago.  It's truly the most versatile group of teas, and the choices available in the West have increased dramatically in the past two decades.  You're missing a wonderful group of teas if you don't take a closer look…and taste.

The character of oolong teas

Oolong teas fall somewhere in-between green and black teas on the spectrum of colors from light to dark.  But that says nothing of their taste.  Oolongs have the widest variation of tastes and aromas of any teas.  They can be citrusy, floral, fruity and sometimes even nutty, woody, or spicy.  Most often it's some combination of these.  Maybe this is the reason I drink more of it than other teas.  For me they span all kinds of weather and moods.  The variations and nuances among the tea's different styles often surprise me, even from one infusion to the next.

The level of oxidation (from 10–80 percent) is the key to the tea's ultimate color as well as the flavors and aromas that are dominant.  Those oxidized the least will be the lightest; those at the high end will be darker.  Floral and citrus notes dominate in lightly oxidized kinds; fruity and nutty characteristics appear with longer oxidation times.  See Basics of Processing for additional details about oxidation.

Because the leaves of finished oolong teas don't even open fully until the third or fourth steeping, they can be steeped eight or nine times depending upon the length of infusion.  They actually get better with multiple brewings.

A Very Brief History of Oolong Tea

Oolong history goes back 300–400 years to the Wuyi Mountains in the Fujian province of China.  This area is less conducive than others for producing green teas, so it's probable that the tea-makers in the area began oxidizing their teas to try to develop a distinct and marketable product. 

The tea next spread south to Guangdong province.  The biggest change in its development, though, came in the mid-1800s after a large population migration took place from Fujian province in China to Taiwan (then called Formosa).  The tea-makers among the migrants integrated their tea-making knowledge with that of the native population and took oolong production to a new level.  In fact, Taiwan perfected oolong manufacture to the extent that the Chinese now imitate the Taiwanese when it comes to producing oolong tea.

These fine teas have really come into their own in the past two decades.  Air transport and better packaging have both made the widespread export of all styles of oolongs more feasible.  Long shipment times took their toll on tea in the past, and faster transportation options have allowed tea-makers to use lighter firings during its processing that retain and highlight the subtle essences developed during oxidation.  The result is that the oolongs we have available to us today have gotten lighter, fresher, more flavorful, and more aromatic.

Where oolong tea is produced

Taiwan and China are the primary oolong producers in the world. Taiwanese oolongs are considered to be the best, but both countries produce wonderful oolongs well worth trying.

However, other countries are also producing interesting oolong teas on a smaller scale.  In just the past year I've tasted nice oolongs from Vietnam, Kenya, and even one from Washington State's Skagit Valley.

What Makes Oolong Teas Different?

Oolongs undergo the processing steps described in Basics of Processing, with some of them repeated.  Ultimately, they require more steps to produce than other teas, and they take longer to produce.  The number of steps they require accounts for so much variation in the teas since it allows for a great deal of individualization among tea-makers. 

Leaves for oolong teas are harvested after the spring greens have been made.  As a result, they are larger and fleshier than those used for other teas, and they contain fewer tannins and less caffeine than younger leaves.  The pluck varies depending upon the type of oolong being made.  It can range from consisting of single leaves to as many as three leaves and a bud, sometimes including the stem. 

Oxidation is the phase of processing that most influences oolong's distinctiveness.  Unlike green teas that don't undergo it at all or black teas that are fully oxidized, oxidation is halted partway through the process when making oolong teas—with the tea-maker determining at which point the ideal bouquet is achieved.  

Oolongs are oxidized very slowly, so their flavors are mellow because a slow oxidation allows the development of thearubigins.  These compounds develop during a long, slow oxidation, and they soften the tea's flavor.

Major Styles of Oolongs

The level of oxidation is the factor to pay attention to if you're just starting to explore oolong teas.  Lightly oxidized oolongs will have floral, citrus, and sometimes herbaceous notes.  In the mid-range of oxidation comes stone fruit essences like peach and apricot, and sometimes they carry spicy and woody notes too.  Highly oxidized oolongs retain the stone fruit flavors and aromas, but they can also be nutty.

Oxidation level also directly influences the infusion color.  Teas with low oxidation times will be light—close to green tea in appearance.  Highly oxidized oolongs will be dark and close to black teas in color. 

Chinese oolongs are traditionally less oxidized than those from Taiwan.  However, both countries produce teas on either end of the oxidation range. 

What to Look for When Purchasing

Depending upon the oolong you purchase, the color of its leaves can be various shades of green, brown, or black highlighted with yellow, orange, red, or even silver. 

Leaves vary quite a bit between different types of oolongs, but they range from a long twist in a gnarled sort of way, to loosely rolled—with or without stems—to tightly rolled. 

The leaves should be fragrant.  Floral or citrus hints should be evident in a lightly oxidized tea.  Ali Shan and Jade Tie Guan Yin (Iron Goddess of Mercy) are two highly regarded lightly oxidized oolongs (10–20 percent).  Expect deeper fruit or spicy aromas in teas with mid-level oxidation (40–50 percent).  Dragon Phoenix and Oriental Beauty exemplify these.  Formosa Oolong is a highly oxidized oolong (about 75 percent), and its leaves should evoke nutty and apricot essences. 

Need other tips when shopping for loose tea?  See How to Purchase Loose Tea.

How to Brew Oolong Tea

If your tea came with specific brewing instructions, it's best to follow them.  They will often recommend initially wetting the leaves with hot water to release the essences, pouring this water out, then fully infusing.  Oolongs require water near boiling to infuse properly.  Most often the leaves unfurl completely only after three or four steepings, so you can get many cups of pleasure from the same tea leaves.

Storage Tips

It's not always convenient to think about the best way to store tea, but it does make a difference in how your tea will taste.  Here's how and why.

It's best to keep oolong teas in an airtight container, at room temperature, and out of direct sunlight.  Keeping it sealed will prevent it from absorbing odors from the surrounding air.  Since tea is usually kept in a kitchen where cooking is done, you can see why this is important.  Limiting its exposure to oxygen will ensure it doesn't continue to undergo additional chemical reactions that can change its taste.  Sunlight will degrade and dry out the leaves.  Heat and sunlight will both destroy the tea's aromas. 

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