How Oolong tea is made
The processing of oolong tea is complex. The crucial part consists in gently bruising the leaves to further the oxidation process. The leaves are then heated to arrest oxidation and dried. Sometimes, after drying, the leaves are also roasted to deepen the aroma and flavour.
The processing and taste of oolong (also 'wulong') teas are located between green tea and black tea. Depending on the type and processing, they combine in different ways the fresh and subtle taste of green tea with the full and strong taste of black tea.
Oolong teas produce an incredible variety of flavours and aromas that no other tea category can offer. Oolong tea is also the only type of tea that produces its own top-quality teas at any time of the year.
Origin and types of Oolong tea
Oolong tea originates in the province of Fujian (China). It is not possible to say exactly when and how this particular processing method was developed. It is assumed, however, that it was created as we know it today in the 17th century.
There are two main growing areas: North Fujian (Wuyishan) and South Fujian (Anxi), which differ greatly in their characteristic aroma and taste. Oolong tea from Wuyishan is also known as Rock Tea and is characterized by a strong roasted aroma. Anxi is famous for his Tie Guan Yin (Tieguanyin), which is slightly oxidized and rarely roasted and therefore rather flowery and fresh in taste.
From Fujian, oolong tea spread further to the south, in particular to the traditional cultivation areas near Fenghuang, Guangdong province, producing Fenghuang Dancong Oolong, or Phoenix Single Bush Oolong.
In the 18th century, the cultivation of Oolong tea also started in Taiwan (Formosa oolong tea). In Taiwan new teas were invented, like Oriental Beauty, high mountain tea and honey scent oolongs, which today are the most iconic Taiwanese oolong teas.
Processing of Oolong Tea
The following process applies roughly to all oolong teas, whether from north Fujian, south Fujian, Guangdong, or Taiwan. This illustrates once again the incredible variety within this tea category, despite the same basic processing technique. Unlike with other tea categories, it is characteristic for oolong tea that only the mature, whole leaves are picked. High-quality, noble varieties as well as the high mountain teas are often still harvested by hand.
Chinese technical terms
- Picking (caizhai)
- Withering (weidiao)
- Resting and shaking (jingzhi and jiaoban)
- Shaking in drum (dalang)
- Piling up / oxidation (duiqing)
- Heating / killing the green (chaoqing)
- Rolling and squeezing (rounian)
- Shaping and drying (zuoxing and ganzao)
→ roughly finished tea (Maocha)
- Roasting (optional)
Steps 2-5 are the heart of the processing of oolong tea. Here the basis for oxidation is laid and the degree of oxidation is determined. With the heating (step 6) the basic character of the tea is fixed; mistakes cannot be corrected anymore. The rest of the processing is just shaping the leaves and refining.
The processing of oolong teas is very complex. It can take up to 24 hours from picking to the roughly finished tea (Maocha). Even today, with modern roasting machines, it can take up to 2-3 days until the refined end product is available. In the past, roasting over charcoal took even longer.
Oolong Tea and Health
Slightly oxidized, "green" Oolong teas such as Tieguanyin and Zhang Ping Shui Xian are richer in antioxidants and stimulate the appetite. Darker oolongs, such as Da Hong Pao and Dong Ding, have on the contrary a warming effect on the body. They stimulate the metabolism and help digestion.
According to Traditional Chinese Medicine (TCM), oolong tea can help burn fat and lower cholesterol levels.
Most dark oolong teas are roasted. As the leaves lose caffeine during the roasting process, these teas may be more suitable for those who are sensitive to caffeine or for evening consumption.