The Making of Oolong Tea in Taiwan

By Catherine Ling - Friday, Jan 16, 2015

Oolong tea is popularly grown and consumed in Taiwan where there is an immensely strong tea culture. With intriguing names like 凍頂 (Dong Ding) or “Frozen Summit” and 東方美人茶 (Dong fang Mei ren) or “Oriental Beauty”, the types of oolong produced by the mountainous island are just as varied as its terrain and soil. The Taiwanese method of production differs a little from China, but generally, the making of oolong tea requires sunning and oxidation before fermentation and roasting.



This is an organic farm in Nantou, the central region of Taiwan. This is one of the farms that supplies SunnyHills Pineapple Cakes with oolong tea.


Peanut shells are used as ground cover to keep the soil moist and the weeds from growing. Soil nutrients are critical – nitrates, phosphorus and potassium are essential – and natural fertilisers from soybean sources may be used.


Tea leaves are best harvested in winter and spring because the temperatures are cooler.


Handpicking tea leaves is backbreaking work, so some farms use machines to trim the top of the bushes.


For the best oolong tea, the farmhands pluck only the bud and two top leaves, nothing more. These newly plucked tea leaves are also the glossiest.


After picking, the leaves are dried outdoors in the sun under muslin shade. They are tossed to ensure even drying. The leaves have to dry in the sun. If it rains, they don’t pluck any leaves.


The leaves are dried for about an hour. They will lose their glossy lustre (centre) but will not be completely dried (left). This stage of drying is so the 儿茶精 essence of tea will be extracted from within cell membranes into the remaining moisture, thus developing flavour.


Then comes indoor drying, which is more gradual but better controlled. The leaves are put on sieve baskets and trays to cool in air-conditioned rooms. This is also where oxidation and fermentation begin. Aware of crushing the leaves, the workers go barefoot or in socks.


The leaves are turned thrice every 1.5hrs for better drying. They are tossed in a special machine to stop enzymatic processes, to break down membranes and capillaries in order to prevent water from further evaporating. Broken leaves will fall out onto the floor. These can be used for tea bags. Only whole leaves are used for loose leaf.


The leaves are then spread out on trays and baskets for three to four hours of fermentation. The workers don’t touch it during this time.


Once the ideal smell is achieved, the tea leaves will be roasted in a giant cylindrical tumbler to obtain their flavour. This process is known as 杀清 (shaqing) or 炒菁 (chaojing). The leaves will go under 260-300 degrees C heat in the tumbler one time, usually at midnight. Tea colour will be affected by the timing. They roast it well for a golden amber colour.


The leaves are rolled and dried on a big machine. Then they undergo a second shaqing about six times on lower heat.


After roasting, they separate and sort the tea into leaves and stems. At the end stage, only 3-5 percent of moisture remains, but the leaves retain their polyphenols.


The roasted tea leaves are compacted and rolled into balls using tightly wound cloth. It takes about 12 hours per batch to do this! The whole process from beginning to end lasts 24 hours, and they can go on for 20 days during harvest season.


Then these tightly wound balls of tea are sent to retailers for baking or 烘焙 (hongpei) in giant ovens. The wholesaler doesn’t determine the final flavour – it is the retailers who develop their own flavour brands.


And there you have your organic spring oolong tea, like the one served to guests at SunnyHillsat #03-05 Raffles Hotel Shopping Arcade in Singapore. For full flavour, the Taiwanese advise that oolong tea leaves be consumed within six months, before a year. Don’t keep the leaves beyond two years.