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About oolong tea & OTPP

In Japan, oolong tea is a familiar everyday beverage. When you think of oolong tea, you might picture a hot beverage, but in Japan, ready-to-drink bottled oolong tea—commonly consumed chilled—is a popular way to enjoy the beverage at home, on the go, and as a companion to delicious food.

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Oolong, black and green tea are all made from the same plant

There is a dizzying variety of teas. Some count more than 1,000 types. But all these teas are made from the same plant, Camellia sinensis, a member of the Theaceae family. Where, then, do the differences between teas come from? The answer is different levels of fermentation(*2) of the tea leaves. To use common examples, black tea is fully fermented, while green tea is not fermented at all. Oolong tea is a semi-fermented tea that has gained popularity as a result of its exquisite level of fermentation. *2 The term “fermentation” on this page indicates reactions such as oxidation.

Oolong tea

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    0% Fermented
    Green tea

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  • oolong tea image

    100% Fermented
    Black tea

How oolong tea is made

Developed over the course of a long history, the technique of making oolong tea is a sophisticated procedure that brings out the finest aromas and the richest flavor from tea leaves. Six key steps, from picking fresh, high-quality tea leaves on a sunny morning, to a careful fermentation process, to final roasting and drying, are absolutely essential to bring out the distinctively rich and smooth oolong tea taste.

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Oolong tea leaves are almost always picked on a sunny morning. The harvested leaves start withering under the sun on the same day they are picked in order to awaken the enzymes involved in the fermentation process that follows.
The tea leaves are transferred to a bamboo basket and shaken, starting with light, damaged tea leaves, to aid fermentation. This process ferments the tea leaf edges.
Pan firing
The fermented tea leaves are roasted in a pan. Heat gradually stops the leaves’ enzyme activity at just the right stage of semi-fermentation.
Rolling the tea leaves while applying pressure and twisting them is what creates the characteristic flavor and aroma of oolong tea.
Cloth ball rolling
In some areas, the tea leaves are wrapped in cloth and undergo further rolling to achieve an even richer and more mellow taste and a special, impressive aroma.
Final drying and roasting
After a slow drying process, the finished product is now ready.

What is OTPP?(oolong tea polymerized polyphenols)

Oolong tea polymerized polyphenols (OTPP), a natural substance extracted from oolong tea leaves, are a category of oolong tea polyphenols that are not found in any other kind of tea. These special polyphenols are formed from the bonding (polymerization) of catechins in the tea leaf fermentation process.

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