Three Days and Two Nights of Flavor Alchemy: The Unique Processing of Taitung Red Oolong
In 2008, Red Oolong was developed through the collaboration of the Tea and Beverage Research Station (TBRS) Eastern Branch, local tea masters, and tea farmers. Its unique processing method, characterized by heavy withering, intense rolling, and deep roasting, was tailored to Taitung's distinct climate, blending a century of tea-making expertise with the region's terroir.
The entire tea-making process spans three days and two nights. Through slow oxidation, the leaves develop layered aromas of flowers, fruits, and honey. When cold-brewed, the tea reveals a sweet and delicate fragrance; when brewed hot, it unfolds deep, roasted notes. Red Oolong stands as a hallmark of tea culture in eastern Taiwan.
The creation of Red Oolong is not merely the development of a new tea variety, but the result of a continuing dialogue between the land, time and the craft of tea-making.
1. Picking
Taitung's tea-producing region lies south of the Tropic of Cancer, within a tropical climate. The weather is warm year-round, which accelerates the growth of tea trees, making it the earliest harvesting region in Taiwan. In the past, it secured a competitive edge in the market by offering "early spring tea", meaning the first fresh leaves of the season.
Red Oolong is typically picked at the stage of one tip with two or three leaves. The optimal harvest window falls between 11 a.m. and 2 p.m., after the morning dew has evaporated, a time when the leaves yield the finest quality.
2. Sun Withering/ Hot Air Withering
The freshly picked tea leaves, known as fresh leaves, are first spread out either under the sun (a process called sun withering), or placed into heated withering machines where warm air replaces sunlight. This begins the first stage of moisture loss through evaporation, preparing the leaves for the next step in processing.
3. Indoor Withering
After sun or hot-air withering, the tea leaves are brought indoors and spread in a thin layer over woven bamboo trays, allowing the moisture to continue evaporating gently.
4. Tossing
At intervals, the tea leaves must be gently stirred by hand to be awakened, encouraging the moisture from the stems to move toward the veins and disperse through the edges. This hand-stirring process is called tossing and is intended to redistribute the stem moisture toward the leaf edges. During this phase, oxidation occurs within the leaves, giving rise to evolving layers of aroma.
5. Big Waving
Withering unfolds throughout the night, and determining the right moments to stir the tea leaves tests the tea master's experience and sense of smell. The leaves must be gently awakened at just the right time to ensure optimal moisture dispersion, removing the raw green note and allowing floral, fruity, and honeyed aromas to emerge. The final stir, known as big waving, requires greater intensity. Traditionally done by hand, this step is now often performed using a panning machine without heat.
6. Heavy Rolling
The preceding steps all follow the traditional oolong tea process. At this stage, however, the method transitions into black tea-style rolling. Rolling involves applying pressure to make the tea leaves rub against one another, breaking down their cellular structure to promote continued oxidation and alter their aroma. This also allows the leaf juices to coat the surface, enhancing the infusion during brewing.
Rolling also shapes the tea leaves into long, twisted strands, preparing them for the subsequent step called cloth rolling. Depending on the condition of the leaves that day, the heavy rolling process typically takes 1 to 2 hours.
7. Supplementary Oxidation
After rolling, the tea leaves are heaped into a small mound and covered with canvas, allowing oxidation to continue until it reaches around 80%—higher than traditional oolong tea, but not quite fully oxidized (100%) like black tea. The oxidation time is adjusted based on the remaining moisture in the leaves, as well as indoor temperature and humidity, typically lasting between 2 to 4 hours.
Proper control of the oxidation duration is crucial. Excessive oxidation can cause the desirable ripe fruit aroma to fade, replaced by sharp, vinegary tones.
8. Panning
Once the tea master determines that the desired aroma has developed, the leaves are placed into a panning machine, where high heat deactivates enzymes, stops oxidation, and locks in the tea's fragrance. The panning time varies between 7 to 10 minutes.
After panning, the tea leaves are spread out to cool in preparation for cloth rolling the next day.
9. Cloth Rolling
The purpose of cloth rolling is to shape the tea leaves into tight, compact ball-shapes, making them easier to transport and store. The process involves wrapping the tea leaves in cloth, compressing and kneading them until they become as firm as stones, then breaking the mass. This cycle of pressing, kneading, and mass breaking is repeated dozens of times over several hours before the leaves finally curl into a refined spherical form.
Each cloth-wrapped tea bundle weighs around 18 to 24 kilograms. Tea makers often develop blisters and calluses from the intense manual labor. Traditionally, this was all done by hand, but today a canvas wrapping-rolling machine assists the process. The tea maker lifts the bundle into the machine and uses a foot pedal to control the rolling speed and pressure.
Withering and oxidation shape the aroma, heavy rolling defines the character, and cloth rolling determines the form.
10. Drying
After cloth rolling, the tea leaves undergo drying to reduce moisture content to below 5%, ensuring stable preservation and uniform dehydration. The drying process must be carefully monitored to prevent loss of flavor. Tea that has completed this stage is called raw tea. At this point, Red Oolong is largely finished, and tea merchants often purchase the raw tea directly for roasting at their own facilities.
11. Roasting
Red Oolong is characterized by heavy withering, heavy rolling, and deep roasting. Roasting is a crucial step in its processing. Depending on style and experience, roasting masters apply alternating high and low temperatures ranging from 70°C to 120°C in a slow, extended roast that often lasts between 20 to 50 hours. This process triggers Maillard reactions and slight caramelization, bringing out sweetness and a rich, mature aroma without any burnt notes.
Traditionally, Red Oolong was heavily roasted. Nowadays, many roasting artisans have shifted toward medium roasts, expanding the flavor spectrum. Roasting also smooths the tea liquor, enhances sweetness, reduces the tea’s moisture content to 2–4%, stabilizes flavor, and makes it more suitable for aging.