Oolong Tea

What is Oolong tea?

Oolong tea (also known as blue tea, or wulong tea) is a semi-oxidised Chinese and Taiwanese tea whose partial oxidation falls anywhere between 10 and 70%. It holds a unique place between green tea (unoxidised) and black tea (fully oxidised), with an aromatic range that spans from the most delicate florals to the deepest roasted notes. Its name means "black dragon" in Chinese, a reference to the twisted shape of the leaves after processing.

The word "Oolong" comes from the Chinese "Wu Long". Several names exist for this family: wulong tea, blue-green tea, or simply blue tea. This variety of names reflects the aromatic richness of the category, with each variety expressing its own character depending on terroir, cultivar and the producer's expertise. For a detailed introduction to this family, its cultivars and processing methods, visit our complete guide to Oolong tea.

Origins and terroirs of Oolong tea

The historical home of Oolong tea is Fujian Province, on the south-eastern coast of China. It was here, in the Wuyi Mountains and around the city of Anxi, that the first oolongs were born in the 17th and 18th centuries. Guangdong, in the far south, also produces oolongs, most notably the Dan Cong teas of Phoenix Mountain, each grown from a single cultivar. In Taiwan, oolong became a true national speciality from the 19th century onwards, when Chinese immigrants from Fujian brought their plants and techniques with them. Today, the island of Taiwan produces some of the world's most celebrated oolongs, including Dong Ding and Milky Oolong Jin Xuan.

Semi-oxidised tea: a balance between green and black

What sets Oolong tea apart from every other family is its semi-oxidation process. After picking, the leaves are first withered in the sun, then gently tumbled to begin oxidation. The tea master then halts this oxidation at a precise moment of his choosing, through a rapid firing that deactivates the enzymes responsible for browning. The resulting level of oxidation, ranging from 10% for the greenest oolongs to 70% for the most roasted, entirely determines the final aromatic profile. The same cultivar can therefore yield two radically different oolongs depending on the producer's decision.

History and heritage of Oolong tea

The story of Oolong tea reaches back to the Song dynasty (960–1279), though the semi-oxidation technique as we know it was codified later, under the Ming and Qing dynasties. A Chinese legend traces its origin to a hunter from Fujian named Wu Liang who, distracted by a deer, forgot his basket of freshly picked leaves. By the time he returned, the leaves had begun to oxidise, giving rise to an entirely new aromatic profile. Over successive dynasties, Oolong became a prized drink among emperors and a hallmark of Fujian, celebrated for its floral fragrances and beautifully balanced flavour.

Its journey to Taiwan in the 19th century marked a turning point for the whole family of teas. Chinese immigrants from Fujian brought with them both the plants and the production techniques, yet the island's humid climate, high altitudes and volcanic soils offered growing conditions unlike anything before. Taiwanese producers gradually developed their own methods: ball-rolled Oolongs, lighter oxidation, charcoal roasting. From this came iconic cultivars such as Jin Xuan (cultivar no. 12, created in 1981 by the Taiwan Tea Research and Extension Station), which gives our Milky Oolong its naturally creamy, lactic notes.

The great varieties of Oolong tea

The Oolong family encompasses around twenty major varieties, each recognisable by its cultivar, terroir or processing method. Here are the most iconic ones you will encounter among enthusiasts and in our own selection.

• Tie Guan Yin: from Anxi in Fujian, a lightly oxidised Oolong with refined orchid notes, one of the cornerstones of the family.
• Da Hong Pao: a grand cru from the Wuyi Mountains (Fujian), prized for its complex mineral aromas and deep roasting, which lends it a distinctive toasted character.
• Dong Ding: a Taiwanese Oolong from the mountains of Nantou, sitting midway between green and roasted styles, known for its balance of vegetal notes and caramel.
• Baozhong (Pouchong): a very lightly oxidised Taiwanese Oolong (10–15%), close in style to green tea, with fresh, floral aromas of great delicacy.
• Dan Cong: from Phoenix Mountain (Guangdong, China), each Dan Cong is grown as a single-plant cultivar and crafted to express a specific aroma, whether orchid, honey or gardenia.
• Shui Xian: a moderately roasted Oolong from the Wuyi Mountains, with mineral and woody notes, a classic of Fujian.

How to Brew Oolong Tea?

Brewing Oolong tea calls for careful attention to both water temperature and steeping time, as its delicate aromas are easily overwhelmed by water that is too hot or a careless measure. The Western method is straightforward enough for everyday enjoyment, while the traditional gong fu cha approach, rooted in Fujian, is designed to draw out the full depth of a fine oolong through a series of short, repeated infusions.

The Western method: simple and approachable

• Use filtered water heated to between 80 and 90 °C, depending on the level of oxidation (the greener the oolong, the lower the temperature).
• Allow 3 to 5 g of leaves per 200 ml of water, roughly a heaped teaspoon per cup.
• Steep for 1 to 3 minutes on the first infusion, gradually increasing the time for subsequent ones.
• The leaves can typically be re-steeped 2 to 4 times, with certain Taiwanese varieties holding up for as many as 6 infusions without losing their character.

The gong fu cha method for exceptional teas

For oolongs of distinction, such as Tie Guan Yin Premium or Da Hong Pao, the gong fu cha method (literally "tea with skill") brings the aromas to life. It calls for a small porcelain or zisha (Yixing clay) vessel, a generous measure (5 to 7 g per 100 ml), and very brief infusions (10 to 30 seconds) repeated 6 to 10 times. Each steeping reveals a different aromatic facet, like a gradual journey into the heart of the garden where it was grown. To explore this further, take a look at our full guide on how to brew oolong tea.

When to Enjoy Oolong Tea?

Thanks to its moderate caffeine content and richly layered aromatic profile, Oolong tea lends itself to almost any moment of the day. In the morning, roasted oolongs and medium-oxidised Taiwanese varieties offer a gentle lift, without the edge of coffee. At midday, more floral oolongs such as Baozhong or Thé Bleu Jianxing make for a refined pause, lovely alongside a pastry or as a digestif. Come late afternoon, softer oolongs are a wiser choice, such as our Oolong fleurs d'oranger, brewed lightly so as not to interfere with sleep.

Oolong also shines as an iced tea, especially in summer: cold-steep the leaves for 4 to 6 hours in the fridge, using 12 g per litre of water. The floral and fruity notes of a Taiwanese oolong are beautifully suited to cold brewing, which removes any bitterness and preserves every nuance of the aroma. Add fresh ginger and a twist of lime for an elegant alcohol-free sparkling drink.

When it comes to food pairings, roasted oolongs pair particularly well with caramel, dark chocolate and dried-fruit desserts, echoing their rounded, toasty notes. Lightly oxidised, floral oolongs find their ideal match in fresh pastries, almond biscuits, macarons and rose or orange blossom entremets. For lovers of Asian cuisine, a plain Oolong tea makes a refined companion to dim sum, steamed dishes and glutinous rice desserts, gently balancing their natural sweetness.

Our Selection of Organic Oolong Teas

Our range brings together around fifteen Oolong teas, chosen for their aromatic diversity and garden quality. From classic Chinese oolongs to contemporary blends and Taiwanese icons, tea lovers will find both pure-origin oolongs and flavoured creations, available in 100 g bags or loose-leaf. Five main families shape our selection: pure Chinese oolongs (Tie Guan Yin, Shui Xian, Fu Liang), Taiwanese oolongs (Milky Oolong, Dongaao), indulgent flavoured oolongs (Peach Vanilla, Almond Chocolate), floral oolongs (Lady Clochette muguet, Fleurs d'oranger) and journey oolongs (Montagne du Tibet, Nepal Jun Chiyabari). Each tea is sourced directly, and the majority of the range is certified organic.

Storing Oolong Tea and Shelf Life

Among all tea families, Oolong is one of the most stable in storage, thanks to its semi-fermentation. Lightly oxidised oolongs keep well for around a year under good conditions, while roasted oolongs are best enjoyed within six months to preserve their signature toasty character. To protect the aromas, store your tea away from light, moisture and strong odours, ideally in an airtight tin kept well away from spices and scented products. Avoid the fridge, as its humidity and ambient smells transfer quickly to the leaves.

Some highly oxidised roasted oolongs can even be aged intentionally: re-roasted every two to three years by a tea master, they gradually develop notes of dried fruit, leather and cacao that call to mind a great aged wine. This tradition, most prevalent in Taiwan and the Wuyi mountains, makes organic Oolong tea one of the rare teas whose aromatic value can actually grow with time, provided storage conditions are respected. For flavoured oolongs and modern blends, however, it is best to enjoy them while fresh, within the year following purchase.

How is Oolong tea made?

Oolong tea is produced through one of the most demanding processes in the world of tea, involving up to eight successive stages whose precise sequence entirely shapes the final profile. It begins with a hand-picked harvest, typically limited to the bud and the first two leaves. The leaves are then withered in the sun to allow some moisture to evaporate, before being brought indoors for an air-withering stage that softens the plant material. Next comes tumbling, the defining step of Oolong production: the leaves are shaken in baskets or gently bruised, which damages the leaf edges and initiates enzymatic oxidation.

The oxidation that follows is the most delicate phase of all. The tea master monitors colour and fragrance closely, stopping the process at the precise moment he has in mind. This is achieved through kill-green: a brief exposure to high heat (pan-firing, steaming, or a mechanical drum) that deactivates the enzymes responsible for browning. The leaves are then rolled, often by hand for premium harvests, giving them their characteristic shape: tight balls for Taiwanese oolongs, twisted strips for Chinese ones. Drying stabilises the remaining moisture. Some oolongs then undergo a final roasting over charcoal or in a drum, developing rounder, more toasted and lingering notes.

The three main oxidation families

The oxidation level, which can range from 10 to 70%, is the most defining characteristic of any oolong. Lightly oxidised oolongs (10–30%), such as Baozhong or modern Tie Guan Yin, retain a leaf colour close to green and offer very fresh floral and vegetal nuances. Medium-oxidised oolongs (40–60%), such as Dong Ding or our Fu Liang Farm, develop fruity notes and a more pronounced body. Heavily oxidised oolongs (60–70%), such as certain Da Hong Pao or roasted Dan Cong, display woody, honeyed and caramel touches that bring them close to black tea, without the bitterness.

Benefits and characteristics of Oolong tea

Oolong tea is recognised by its twisted leaves (in Chinese varieties) or tightly rolled balls (in Taiwanese ones, such as our Milky Oolong), ranging in colour from deep green to amber depending on oxidation. Once brewed, the liquor is clear and bright, in shades of gold to amber. Its aroma is complex, moving between floral, fruity, sometimes woody or roasted notes. On the palate, it combines the freshness of green tea with the depth of black tea, with a silky quality unique to semi-oxidised teas.

From a nutritional standpoint, Oolong tea provides antioxidant polyphenols (catechins, theaflavins, thearubigins) that help the body combat oxidative stress, as noted by the EFSA. It contains a moderate level of caffeine (15–30 mg per 200 ml), balanced by L-theanine, an amino acid with relaxing properties that softens the stimulating effect. Oolong tea is also known for its digestive properties: some studies suggest it stimulates digestive enzymes and reduces bloating after fat-rich meals, though it does not constitute a medical treatment. To explore these effects further, visit our dedicated page on the benefits of Oolong tea.

Oolong tea and metabolic support

The landmark study Rumpler et al., 2001, Journal of Nutrition highlighted a modest increase in energy expenditure among regular Oolong tea drinkers, linked to its polyphenols and caffeine content. These effects remain limited and are not a substitute for a balanced diet or regular physical activity. They are meaningful only as part of an overall healthy lifestyle.

Oolong tea, green tea and black tea: what sets them apart?

The Oolong tea family is best understood in relation to its two neighbours. Green tea is fixed immediately after harvesting, with no oxidation: it retains the fresh, vegetal character of the leaf but tends to have a lighter body. Black tea, on the other hand, is fully oxidised, developing malty, honeyed and woody aromas while losing much of its floral complexity. Oolong sits precisely at the intersection: a lightly oxidised oolong can evoke a very aromatic green tea, while a roasted oolong approaches the rounded depth of black tea, without the bitterness. It is this aromatic versatility that makes Oolong the most diverse and endlessly fascinating family of tea for enthusiasts.