White Tea Processing Techniques

The production process of white tea generally consists of two steps: withering and drying, with withering being the key stage.

Withering can be divided into indoor natural withering, mixed withering, and heated withering. It must be flexibly adapted to the climate, and for sunny spring and autumn days or clear summer days without oppressive heat, indoor withering or mixed withering is preferred.

The refining process involves removing stems, flakes, wax leaves, red leaves, and dark leaves, then baking over a gentle heat until sufficiently dry. This enhances the tea’s aroma with a subtle roasted scent. When the moisture content reaches 4%–5%, the tea is packed while still warm. The hallmark of white tea processing is that it neither destroys enzyme activity nor promotes oxidation, instead allowing for mild natural oxidation while maintaining the delicate aroma of the tea buds and a fresh and brisk flavor in the brew.

- Picking
White tea is picked when temperatures allow for tender, fresh leaves with one bud and one unfolding leaf in a jade white color. The process involves picking early, picking tender leaves, picking frequently, and ensuring clean picking. Buds and leaves must be uniform in size and shape, and the stems kept short. The tea is handled gently during harvesting, placed lightly in bamboo baskets, and transported in bamboo containers.

- Withering
Freshly picked leaves are spread evenly on bamboo trays in a thin layer and should not be disturbed. After spreading, the type of withering—indoor natural withering, mixed withering, or heated withering—is chosen based on the climate conditions and leaf grade. When the leaves are 70%–80% dry, both indoor natural withering and mixed withering require sieving.

- Drying
Initial drying: Dryer temperature at 100–120℃ for 10 minutes. Cooling: Spread and cool for 15 minutes. Re-drying: Dryer temperature lowered to 80–90℃, with low-temperature long drying at around 70℃.

- Storage
Dried tea leaves should have a moisture content of 5% or less and be stored at room temperature.

Processing Bud Tea: Weather and Temperature Are Key

Tea buds should be spread thinly and evenly on a water sieve (a large bamboo sieve with wide openings, about 100 cm in diameter and each hole approximately 1.4 cm square with bamboo strips about 1 cm wide). The buds must not overlap, with about 250 grams of buds spread on each sieve. After spreading, place the sieve on racks to sun-dry, ensuring the buds are not disturbed to avoid mechanical damage that could cause reddening.

On sunny and clear days, drying for one full day can achieve 80%–90% dryness. The buds are then baked in drying baskets lined with a layer of white paper on the baking surface. Each basket can hold 125 grams of tea buds, with the baking temperature kept between 30–40℃. If the temperature is too high or the buds are layered too thickly, the buds will scorch and turn reddish-brown with an impure aroma. If the heating is not sufficient, the buds may turn black, while excessive drying may cause the bud color to turn yellow and lack their desired white appearance. When it is humid or rain prevents proper drying, a day’s sun-drying may only reach 60%–70% dryness.

Further sun-drying on the following day is necessary to achieve 80%–90% dryness before proceeding to the drying step. If sun-drying cannot proceed due to rain after reaching only 60%–70% dryness on the first day, the tea buds should be dried that evening or the next day with gentle heat at temperatures of 40–50℃. In windy and dry weather, the tea can be withered indoors until it loses about 30% of its weight, then baked slowly over gentle heat until dry.

Processing Leaf Tea: Unique Mixed Withering

After harvesting fresh leaves, place about 300 grams per sieve on water sieves. Holding the sieve with both hands, rotate it to spread the buds and leaves thinly and evenly, ensuring no overlaps. This process is called “opening green” or “opening the sieve.” Once spread, place the sieves on cool racks in a well-ventilated withering room.

Do not disturb the leaves, and allow them to wither for 35–45 hours, until the buds and leaves turn silvery white, the leaf color darkens, and some leaves stick to the sieve, a state referred to as “sticking to the sieve.” The tips of the leaves curl up, commonly known as “curling tails,” with edges slightly curling inward and fine wrinkles appearing on the surface.

Once the fresh green aroma dissipates, two sieves can be combined into one (because the leaves shrink during withering and will no longer fill the sieve’s surface, potentially causing the edges to dry out or hinder moisture loss). Combining also prevents the leaves from drying into flat, unappealing shapes. Withering continues until the moisture content reaches about 22%—this is referred to as “80% dry.”

Afterward, the leaves are combined into one sieve again, withered for an additional 10 hours, and dried to a moisture content of about 13%, also called “95% dry,” which produces properly withered raw tea.

The optimal withering period depends on the temperature and humidity and cannot be generalized. Practical experience suggests that indoor withering typically lasts 48–72 hours. If the weather turns overcast and cold midway through, leaves at 80% dryness may be stacked thicker. If the withering is lighter, stack thinner layers.

If withering only reaches 60%–70% dryness, drying should be done in two stages: initial drying at a high temperature (100℃) until 80%–90% dry, followed by cooling and re-drying at a lower 80℃. If the withering period is too short (less than 24 hours) or insufficiently done, resulting in a weight loss of less than 40% before drying, the final tea will develop a parched green color, gradually turning yellow-green, with a raw, astringent flavor that does not meet white tea standards.

Conversely, if withering is carried too far and exceeds 72 hours, the finished tea color will turn dark and dull, with a poor fragrance or even a moldy odor.

Mixed Withering: A Special Technique for White Peony and Tribute Eyebrow Tea

For these teas, mixed withering combining sunlight and indoor methods may be used. Its advantages include shorter withering times and enhanced tea liquor smoothness. Sun exposure is limited to early morning or late afternoon in spring when sunlight is mild, lasting 20–25 minutes and not exceeding 30 minutes.

After sun exposure, the tea is immediately moved indoors for natural withering. This process may be repeated 2–4 times as needed, until the desired effect is achieved. However, mixed withering requires precise control over quality and is generally avoided.

Heated Withering (Using White Peony as an Example)

In recent years, the Bailin Primary Tea Factory in Fuding has adopted the technique of blowing warm air into the withering room for fresh leaf withering. The room temperature is controlled at 22–27℃, with relative humidity held at 60%–75%.

Withering lasts 25–30 hours, after which the leaves are removed and stacked for 3–4 hours. At this stage, the main veins of the leaves turn reddish-brown, the leaf color darkens, the grassy smell disappears, and a fresh and sweet fragrance emerges.

Low-temperature drying (around 80℃) is then conducted for about 25 minutes. High temperatures will cause the white fuzz on the leaves to turn yellow. This method of blowing warm air during indoor withering produces finished White Peony tea that retains its traditional style and quality comparable to naturally withered products, while significantly reducing production time and avoiding weather constraints.