Discovering Oolong Teas: Origin, Flavour, Benefits and More

Still little known in France, blue tea, also called oolong, is a truly refined leaf. It delivers a soft infusion, with very little bitterness and a low caffeine content. Its leaves undergo a partial oxidation that varies from one method to another, producing teas that sit somewhere between green and black tea. The result: brews with remarkably diverse flavours and aromatic notes. Ready to unwind with the jasmine fragrance of a blue tea?

Origin and character of blue teas

In France, we tend to know black, green and white tea well. Yet blue tea remains far less familiar. This fragrant tea belongs to the very same family and comes from the same plant: Camellia sinensis.

Oolong: why is it called blue tea?

The name blue tea refers to the colour of the leaves once infused, not to the colour of the liquor. Blue tea should not be confused with butterfly pea flower infusion. The butterfly pea is a plant of the Fabaceae family and has nothing to do with the tea plant. Its flowers produce an infusion of a striking blue hue.

Where does blue tea come from?

Oolong tea has its roots in China, in the Fujian province. Its cultivation has also flourished in Taiwan. Today, around thirty countries produce blue teas, including India, Vietnam and Malawi.

What makes oolong tea different from other teas?

The originality of oolong lies in the semi-oxidation of its leaves. Indeed, the oxidation level of blue teas ranges from 10 to 80%. These teas therefore sit between green tea (no oxidation) and black tea (fully oxidised leaves). For blue tea, the larger, more mature leaves of the plant are used, leaves that are lower in tannins and caffeine. Oolong teas reveal a broad palette of flavours and aromas, shaped by the garden of origin, the leaves selected, the oxidation method and even the way the leaves are rolled.

Oolong tea: from plant to cup

Like other teas, blue tea goes through several stages of transformation.

• The withering of the leaves, lasting from one to four hours.
• Oxidation of the leaves, of varying length. This key stage releases the aromatic notes of the tea.
• Firing: the leaves are heated to 200°C to halt oxidation.
• The rolling of the leaves into pearls, twists or simply crumpled shapes.
• A final drying at 100°C, which stabilises the tea by drawing out the remaining moisture.
• Packaging into pouches or tins.

Each country has its own oxidation technique, yielding a very different tea. In China, blue tea is lightly oxidised, between 10 and 25%. Only the edges of the leaf turn brown, while the heart keeps a lovely green tone. In Taiwan, oolong is oxidised between 60 and 80%, and the whole leaf shifts in colour.

Brewing and tasting blue teas

Now to enjoy the flavour, fragrance and benefits of a blue tea infusion. Time for Tea Time!

Brewing oolong tea leaves

For oolong, allow 12 grams of leaves per litre of water, or 3 grams per cup. Infusion lasts 1 to 7 minutes, depending on your taste. The ideal water temperature is 80°C. Boiling water is best avoided, as it overwhelms the delicate flavour and diminishes the plant's qualities. Multiple infusions are very much possible with oolong, each one revealing different notes. In China, oolong is brewed in a white gaiwan, the better to admire the colour of the liquor.

Flavour and fragrance of the infusions

The infusion reveals a soft liquor, without bitterness. The flavours and aromas of blue teas vary according to the garden of origin, the degree of oxidation and the level of firing.

• A lightly oxidised blue tea comes closer to the character of green teas, with floral notes recalling jasmine, orchid, lilac or peony. The vegetal liquor can be carried by indulgent aromas, sweet or even buttery. At times, the cup unveils hints of coconut or vanilla.
• A medium-oxidised blue tea offers a cup with dominant notes of fruit, honey and spice.
• A highly oxidised blue tea draws closer to black tea. You can detect woody and toasted notes, reminiscent of warm chestnut or hazelnut. A flavour of ripe or candied fruit comes through (prune, red berries, grape and more). The amber liquor may also reveal a touch of honey.

Blue teas: gentle benefits for wellbeing?

Enjoying a cup of blue tea at Tea Time is also a way of caring for yourself. Beyond its low caffeine content, oolong tea releases cis-jasmone and methyl cis-jasmonate. These compounds, with their soft jasmine fragrance, are thought to support relaxation and sleep.

Oolong: a few teas to discover

Not yet familiar with the varieties of oolong tea? Here is a short selection of well-known and widely enjoyed infusions.

• Milky Oolong: its lightly oxidised leaves are placed above steaming milk. Milky Oolong tea absorbs the milky fragrance and releases it delicately in your cup.
• Tie Guan Yin: the traditional blue tea of China, with its signature floral notes.
• Bao Zhong: a blue tea typical of Taiwan, subtly scented with jasmine.

The family of blue teas has many surprises in store. Curious to explore the colours and aromas of a blue tea from China or Taiwan? Find your pouch or tin among our oolong teas.