Every type of tea we drink comes from the same plant, Camellia Sinensis. But what makes them different is not only the plant growing conditions but particularly its production method.
This last factor will determine the type of tea and its organoleptic properties. The main tea categories are white, yellow, green, blue (Oolong), black and dark (puerh). So, aiming to release the best properties according to the type of tea obtained, there are two elements that are close enough to mention: water temperature and steeping time.
And even if every producer has its own method production, the common processes for determining the teas’ type are the following: plucking, withering, rolling, oxidation and drying. By the way, it is meaningful to highlight that not necessarily all teas are passed by all these stages.
White tea
This is the less processed tea which leads to be the most delicate in flavour and aroma.
It is produced from young buds of still undeveloped leaves and the youngest white leaves covered with silvery hairs. As it is lightly oxidized, its flavour could go from subtle floral to sweet.
After plucking the leaves/buds carefully, they are withered. During its process, it is prior to constantly control the temperature, moisture level and ventilation. The leaves are spread on bamboo racks, where they will lay for the following 3 days. The oxidation level reached is only between 8 to 15 percent. This way, a little oxidation is normal but not promoted. Once withering is finished, the leaves are sorted according to the desire grade and broken leaves are removed.
One of the most known white teas is the Bai Mu Dan, which originally comes from Fujian, China.
Steeping time and temperature: 3 to 6 minutes at around 70° C.
Yellow tea
This is the less known and relatively uncommon type of tea. The leaves are involved in a particular process called Men Huang, which means heaping or sealing yellow and causes slight oxidation.
Once leaves are already plucked, they are withered lightly and heated to avoid oxidation. During Men Huan process, leaves are slightly steamed and wrapped in wet fabrics and left for 5 to 10 hours.
This wrapping method creates the proper temperature and atmosphere for a light oxidation and aromas development. Then, their leaves are dried at high temperatures to reduce its moisture content up to 5 per cent. Finally, leaves are sorted.
A renowned yellow tea is Meng Ding Huang Ya from Sichuan Province, China.
Steeping time and temperature: 2 minutes at 75° C.
Green Tea
Its characteristic green colour is due to an early stop oxidation process right after plucking, which has to be in the next few hours once they are off the plant. This is why green teas have a wide range of vegetable, toasty, sweet and grassy flavours. After the leaf is plucked and lightly withered, oxidation is prevented by heat. Then, leaves are rolled and dried.
Thus, heat in this type of tea is crucial and unlike other teas, oxidation is not promoted in any way. In addition, heating can be done in different ways, depending on every farm traditions or what kind of green tea is preferred.
To release their aromatic oils while giving the leaves the shape desired, leaves are rolled. Then, its moisture content is reduced to around 3 to 6 per cent. This leads to stopping any further chemical reaction while stabilizing tea.
Some of the most well-known green teas are Houjicha and Genmaicha from Japan.
Steeping time and temperature: 1 to 3 minutes at 60-80° C.
Oolong
This kind of tea has a complex production method which involves a long and carefully withering process. Moreover, it is a partially oxidized tea (15 to 80 percent), depending on the process. This is the primary reason why it can be found a wide range of flavours. Thus, from sweet and fruity to woody and toasty flavours are encompassed.
After plucking, it is selected one bud every 3-5 leaves. They are briefly withered before oxidation is promoted. This process is repeated times until the leaves get the desired level of oxidation. After this, heating will help to stop the oxidation, which can be done using traditional or modern techniques such as hot pans or rotating cylinders.
Then, leaves are rolled and given a shape. And finally, tea is dried or fired (some are even baked) at high temperatures to stabilize it.
A distinguished Oolong tea is Da Hong Pao, from China and High Mountain Tea (which refers to certain varieties of oolong tea grown in the mountains of central Taiwan).
Steeping time and temperature: 45 seconds to 1,30 minutes at 88-95° C.
Black tea
It is the most oxidized tea and its flavour can be defined as strong, intense, robust, malty and bitter. After plucking, leaves are withered for about 3 to 20 hours before being rolled to encourage oxidation. When the right level of oxidation is reached, leaves are dried to stop oxidation and stabilize the leaves. The leaves are sorted depending the final product desired.
Even if this tea has high levels of oxidation, it is not fully oxidized due to this could lead to losing desirable flavours.
Not only famous but also highly recommended is the Lapsang Souchong from Fujian Province, China.
Steeping time and temperature: 1 to 3 minutes at 85 to 95° C.
Dark tea
The only type of tea that is ferment. Thank to this, its flavour can vary from earthy and rich to smooth and complex. In general terms, the processes involved are withering, heating, rolling, heaping and fermentation. Heaping implies the leaves to be piled up and covered while they settle where the temperature and humidity are closely controlled the next days.
Pu-erh of Yunnan, China is one of the most recognized.
Steeping time and temperature: 1 to 3 minutes at 90 – 98° C.
Considering that there are multiple productive processes and possible scenarios where the fresh leaf goes through in order to become a particular type of tea, further sub classifications are wider and complex. By the way, this would not be considered as an overwhelming fact. On the contrary, this is the starting line of a fascinating and rich tea world.
References:
- C, Roberson. (2000), White tea (China)from Usenet's rec.food.drink.tea
- H, Gascoyne; J, Kevin; Marchand, François; Desharnais, Jasmin; Americi, Hugo (2011). Tea: History, Terroirs, Varieties. Richmond Hill, ON: Firefly Books.
- L. Heiss; R. J. Heiss. (2007).The Story of Tea: A Cultural History and Drinking Guide.