All About Chinese Tea, Part 1
Thursday, 16th July, 2009 - David Farmer
I was fortunate to spend time in China in the late 1970's and early 1980's which came about from one of the poorly thought out business ideas of my brother and I to import tea from China. What follows comes from notes I took during an extended stay in June, 1980. I believe this information will prove quite useful to those who love tea and its many types.
A. A Brief History of Chinese Tea
Tea bushes grow wild (Camellia sinensis) in the western part of Yunnan province. The use of tea as a medicinal or herbal drink and the eating of fresh leaves for medicinal reasons is older than 4500 years. Tea trees as old as 800 years are still growing in Yunnan province. In the Shi Huang Dynasty (259-210 BCE) tea was exported for the first time and was seen as an essential medicine being taken abroad by traders to Malaysia and Thailand. Also by the last few hundred years BCE tea was being drunk as a beverage and the cultivation of the tea bush had commenced.
In 780 CE Lu Yu wrote "The Classic of Tea" which set out in detail all that was known about cultivation and manufacturing of tea and the accepted custom of drinking tea. The Tang Dynasty (618-907 CE) was a period of active development of the tea industry and by the 8th Century the basis of the modern tea industry had been established.
Tea at this time was steamed green tea, a method still used in Japan. It was transported in large compressed blocks. About this time the pan frying of green tea was developed which led to a great improvement in quality. The period of the Sung to Yuan Dynasties (960-1368) saw the development of tea as a major export commodity to countries such as Malaysia and Japan. From the 8th to 11th Centuries flavoured teas began to appear of which the most important was the development of Jasmine tea. The discovery of fermentation and thus the production of black tea began in the early 17th Century. The semi-fermented Oolong tea styles are dated from the middle of the 19th Century.
By 1640 tea was being exported to Arabia, Africa and Europe. By the early 18th Century Guangzhou was exporting 20,000 tonnes per year. Chinese tea exports steadily increased and in the peak years of 1880-1888, 120,000 tonnes were exported each year. In 1886 the peak year, 134,000 tonnes of both black and green tea was exported. These exports figures were not reached again and during World War II total Chinese tea production was as low as 10,000 tonnes. It has since bounced back and was 800,000 tonnes in 2004.
B. The Tea Bush and its Distribution
Tea is grown in many Chinese provinces of which 14 are significant these being, going from south to north; Yunnan, Guangxi, Guangdong, Huizhou, Hunan, Jiangxi, Fujian, Sichuan, Hubei, Anhui, Zhejiang, Jiangsu, Henan and Shandong. Significant developments are the establishment of tea gardens in the high steppes of Xizang (Tibet) along the river valley south of Qamdo and in the provinces of Shaanxi and Gansu.
Tea has the botanical name of Camellia sinensis. Two varieties are recognised, Assam (or Yunnan as it will be referred to) and Chinese. The Yunnan variety is a large, thick leaved plant which grows in tropical to sub-tropical climates and is killed by frosts. It thrives in southern China in the provinces of Yunnan, Guangxi and Guangdong, and selected areas of other provinces. It is used mostly to make black tea and produces a deeply coloured tea of strong taste with a tough tannic finish. As these are the requirements of the western tea drinker it is widely planted. Green tea made from Yunnan leaf tends to be bitter and over coloured. Most Indian tea is made from Yunnan and this accounts for the poor quality of Indian green tea.
The Chinese variety has a smaller leaf than the Yunnan and because it is frost tolerant is widely grown being the main tea bush of China. In the southern provinces it is grown at higher altitudes. This variety makes a softer, more fragrant tea than Yunnan and is the favoured green tea variety. It also makes the famous 'hand made' black teas of China such as Keemun. These are fragrant teas with delicate flavours which are masked with the addition of milk and sugar.
As well there may be a third variety called the medium leaf variety but its status is uncertain and as well new varieties are being developed.
C. Manufacturing Tea
There are two basic methods to make tea. To make green tea the freshly picked leaf is heated or 'fired' to destroy leaf enzymes which combine with oxygen to chemically alter the leaves. This method can be compared to snap freezing, the idea being to retain colour and the green freshness of the leaf.
The second method makes black tea and enhances the leaf enzymes to react with oxygen and chemically alter the leaf in a process known as fermentation. This requires four steps.
1. A withering stage in which the newly picked leaf is placed on racks and draughts of cool air reduce the water content by 20% to 40%. The leaf becomes limp and pliable and this process it seems starts a chemical alteration in the leaf as black tea made from unwithered leaves has a bitter or brassy taste.
2. A rolling stage where the pliable leaves are rolled back and forth in a manner that breaks the internal cell structure but does not break the outside leaf cuticle. This rolling action creates a mixing of leaf enzymes, with oxygen, and other leaf chemicals-principally polyphenols or tannins. If withering is not done correctly when its rolled the leaf disintegrates. Rolling is done by placing the withered leaf between two metal plates of variable sizes though the ones observed were about two metres across. These plates move eccentrically to each other while at the same time pressure is applied to the leaf mass. The time taken to roll the leaves and the amount of pressure applied has a considerable effect on the final quality. Once this rolling would have been done by hand. In a modern tea factory this rolled leaf may also be cut or sliced. This leads to a stronger flavoured and deeper coloured tea and a tea which draws more quickly, features wanted by western consumers. For tea bags this cutting stage turns the leaf rolls into very small particles so they draw very quickly in the cup.
3. The third stage assists the chemical alteration by placing the rolled leaf into a fermentation room of constant temperature and humidity. The time at which fermentation should stop is determined by experience but generally happens when the leaf has turned a copper brown colour.
4. The final stage is firing the leaf at a temperature which halts the fermentation reaction and reduces the leaf moisture to 3-4%.
Variations to these basic steps produce the many sub-varieties of tea known as semi-fermented teas such as oolong and puerh tea.
D. The Varieties of Tea
How tea is made is a convenient way to divide tea into groups.
These are the green teas of which there are two types; the traditional pan fried teas and the mass produced fired green teas. A third variety would be the steamed Japanese teas.
These are the Oolong teas in which fermentation is stopped at an early stage.
These are the black teas of which there are two types; the traditional leaf or congue teas and the modern style of 'broken leaf' teas. The congue teas are the famous black teas of China. They are made from the Chinese variety although in Yunnan they are also made from the Yunnan variety.
Congue teas are rolled several times under little pressure and unlike the broken teas do not pass through a leaf cutting machine. They are made from the tenderest leaf and are much more expensive to produce than broken tea. Broken teas are not withered for the same length of time and are rolled and cut quickly. Some broken teas are now made which are not withered or rolled. With congue tea every effort is made to keep the leaf intact whereas with broken teas the leaf is deliberately broken, cut and macerated. Congue teas can be graded by their appearance whereas broken teas require tasting. Examination of the tea after drinking will tell a lot about the quality of the leaf.
Post Fermentation Tea
This is a small group to which belong the compressed teas and Pur-Eh (Irk) tea. Fermentation continues at a very slow rate for years after production. They are made from the Yunnan variety like a green tea, but is not fired to the same temperature, hence the moisture content is higher which allows for continuing slow chemical changes.
Scented and Flavoured Tea
Both green and black teas can be scented after production with flower buds. The most famous is Jasmine green tea, and other varieties rose black tea, orchid green tea, lichee black tea, Oolong scented tea and jasmine black tea. Lapsang Souchong is a special type of scented tea in which pine scent is introduced at the withering stage by the burning of pine chips beneath the leaf. Tarry Souchong is an artificial Lapsang in which good congue black tea is smoked after making.
Interestingly the Chinese do not make a lemon scented tea except in an instant powder form and they also do not make an Earl Grey style which is scented with bergamot oil.
There are several other teas made like green tea and these are the White tea of Fukien province and Yellow tea of Hubei province.
E. What Makes Good Tea.
Many physical factors such as soil type, climate, and the time of picking affect quality. Also to be considered are processing variables and the age of the tea when drunk. Good tea is picked with two leaves and the bud and the final quality then depends on the quality of this original leaf. Factors that are important are as follows.
Climatic and Seasonal Effects
The finest teas are made from bushes growing above 1000 metres although there are some exceptions. In southern China and Sri Lanka the best teas are made in autumn (September to October) after the monsoonal rains. In northern China the best teas are made in spring during April and May, when the first new shoots appear. Tae is picked for about seven months though within that time there are several favoured periods for a flush of leaf growth which makes better tea. In Guangdong province the best tea is made in autumn, the summer tea is very strong and both are better than tea made in spring.
The best tea such as pan fried green teas, the grade one congue teas and the flowery broken orange pekoe, FBOP, will always be made at a select time of the year from the best leaf. The high quality bud has higher percentages of chemicals that give the desirable brisk taste, while young leaves give greater strength. A factor that increases quality by producing better bug growth is fertilisers.
The production of black tea and green tea can affect the grade, style and quality of tea. While mechanisation of the Indian tea industry commenced about 1870 China commenced making broken teas later than India. Before 1960 black tea was made in the way that is only used today for congue teas. Mechanical rolling of tea and cutting produces a darker coarser tea with less aromatics and more strength and this coupled with Indian tea being made from Yunnan leaf (= Assam leaf) would have produced a darker more tannic tea than the Chinese were making. It is interesting to speculate that with the increasing use of milk and sugar the Indian teas slowly developed a commercial advantage.
In "The Tea Industry of India", Baildon, 1877, says; "the reason for panning (referring to pan firing)is to tone down the harsh rough flavour of the tea, so as to make it mellow to the palate. Now as I said before, sufficient tasty, aromatic tea reaches the home market from China, without it being necessary to increase the stocks by exportation from India. Considering that teas from this country are invariably used for strengthening the China article, rough, malty strength is principally required, and as such is sent no complaint will ever be made I fancy; unless indeed India tea is drunk alone, and then a little panning is not out of place."
With the success of tea bags this trend has continued and has made the tea industry change perception of what is quality; traditional quality or consumer driven quality. It is perhaps arguable whether the best congues are better than the best FBOP grades.
It is in making the everyday black teas that machinery is so important. Too fine a cutting may release too much catechine which gives a bitter taste and if fermentation is not stopped at the right time the tea tastes plain, and the liquor is not bright.
To control fermentation which will commence in the rolling stage it is now realised that air conditioning is necessary to regulate the temperature both at this stage and during rolling.
The Storage Factor
Tea should be drunk in the year it is made. Oxidation continues at a very slow rate in dry tea and there is a slow loss of delicate aromatic flavours with age.
F. The Grading of Teas
i) Pan fried leaf
ii) Fired leaf. Only two grades are recognised; leaf grade and fanning or broken grade.
i) Congue grade. These are subdivided into some five grades. The top grade comprises about five percent of the total production and is made of uniformed sized pieces. The lowest grade contains broken pieces and dust.
This type of tea is also made in Darjeeling and Sri Lanka where they are called FOP (flowery orange pekoe) of FP (flowery pekoe). The Sri Lanka teas are not as refined as the Chinese containing more stalks.
ii) Broken tea. The best grade is FBOP (flowery broken orange pekoe), then BOPF (broken orange pekoe fannings), BOP (broken orange pekoe), F (fannings) and Dust. The grade BP (broken pekoe) is kept separate and is of low quality.
To understand this grading system it is necessary to realise that at various stages of the rolling the leaf may be separated according to size. Thus large unbroken pieces are put back into the rollers while small tender fragments are removed and perhaps rolled separately or sent straight to the fermentation room. While good congue grades and FBOP contain large pieces of uniform size (one centimetre long), size is not a determining factor with the other grades. Thus the fine size BOPF may be composed of tiny fragments of very tender leaf buds and leaf tips and be of superior quality to a BOP. The grade BP is always low grade being made of those pieces of toughened stem and old leaf that will break up with rolling.
With grading it is also necessary to know the origin (locality of the tea garden) of the tea due to the taste difference of various regions. Mr. Cheng Kuo-Chan (Shanghai Tea Branch) told me of an interesting way of distinguishing between the liquor of congue and broken teas. After sitting for about two hours in a cold room, broken teas develop a creamy scum on the surface that is rarely found with congue tea.
The grading of these teas is different, as the appearance of the tea is not considered important. Old and new leaf and stalks are kept together. Roller breakers are not used. Even so dust and fannings are removed. These teas are principally graded on taste.
To be continued:
Including the specialty teas of china, tasting and drinking tea, and detail on the growing and making of all types of tea including a long passage on jasmine tea.