• HOME >
  • Tea constituents and functional effect

The color can tell the quality of black tea

[2013.06.29] Posted By

the leaf color is essential to judge the quality of black tea
The well-fermented black tea and the poorly fermented black tea have very noticeable difference in flavour. The well-made black tea produces a sweet flavour, while the poorly made black tea produces a sour or musty smell.

Observing the colour, knowing the skill

In addition, the liquor of the tea will show the effects of the fermentation. The well-fermented tea would produce a reddish liquor with yellow hue, while the poorly fermented tea would produce a brown liquor. Besides, the difference in colour was not only visible in the liquor, but it affects the brewed leaves too. As a matter of fact, there is an obvious difference in the constituents between the well-fermented tea and poorly fermented tea.

The well-made black tea contains theaflavin

It is often said that the main constituent of black tea is tannin. However, the tannin is the “general name” of a substance formed by the oxidation and conjugation of a plant’s polyphenols. Any substance can be called tannin as long as it consists of high molecules and produces a brownish colour. To some extent, the substance contain in green tea are also called as tannin in some tea book. Since the word tannin lacks clear definition creating confusion among tea folks, I try not to use this term when describing the fermentation of tea.

The main substance in a well-processed black tea is the theaflavins. There is variance of theaflavins depending on which polyphenol it is made from. It is formed by the conjugation of 2 to 3 flavonoids and is mediated by the oxidation enzyme which produces the substances that show bright yellow colour. It is known that a cup of fine black tea shows a golden ring at the wall of the tea cup. This golden ring is formed with yellow pigments, i.e., the theaflavin.

Thearubigin is the symbol of failure in fermentation

If the fermentation was not well managed, the theaflavin would conjugate each other and form a larger molecule substance. These substances do not have a specific structure and there are thousands or millions of different substances. These substances are called thearubigin. Once this substance is formed, the tea would produce an unpleasant flavour simultaneously.

The process of black tea requires very delicate handling

The fresh tea leaves contain polyphenols. During fermentation (oxidation), the polyphenols are conjugated and formed theaflavin. However with additional oxidation, the theaflavin will be converted into thearubigin.

Polyphenol >> Theaflavin >> Thearubigin

When minor errors occur during the process, the theaflavin goes too far and instantly produce thearubigin. This reaction is irreversible. Therefore, the production of black tea is very difficult and it requires a lot of experiences and know-how to control the process precisely. The process of black tea consists of withering, rolling, fermentation and drying. In fact, besides the importance of the fermentation process, manufacturers have to pay more attention to the entire process to ensure that the leaves are not over fermented.
It is very easy to tell the quality when you observe the brewed leaves. The brewed leaves of well-processed tea will be of bright orange-brown colour, while the poor quality tea is of dark brown.

The leave color is reflected from the fermentation

Related Articles

How to get the latest update on HOJO Tea?

1. Follow Twitter, 2. Click "Like" on Facebook, and 3. Subscribe in newsletter. You can have the latest tea news from HOJO Tea.

Subscribe the Newsletter to enjoy the privileges
You may receive a free sample upon purchase, or you may have the priority to purchase special products. So please remember to subscribe our newsletter as well as the social network.
  •                 

HOJO TEA Online Shop NEWSlist

New Release of Li Xiang Bai Mu Dan White Tea
We released a new white tea, called Li Xiang Bai Mu Dan …
New Release of High Mountain Purple Black Tea
We have released High Mountain Purple Black Tea. It is …

NEW ARTICLES

Cooling speed of water differs depending on the volume of teapot
The smaller the size of teapot the faster the temperatu …
New Release of Li Xiang Bai Mu Dan White Tea
We released a new white tea, called Li Xiang Bai Mu Dan …
A Shiboridashi, the perfect alternative of a Gaiwan
Shiboridashi is one of the tea brewing equipments. In J …
New Release of High Mountain Purple Black Tea
We have released High Mountain Purple Black Tea. It is …
Do you know that the taste of water varies everyday?
You might have noticed that the taste of tea is not the …
New Release of Guo Gan Ripe Pu-erh from Myanmar
We released ripe pu-erh tea produced in Myanmar from th …
New Release of 11 Years Vintage Tea Aged in Malaysia
We have just released 4 types of 11 years aged vintage …
New Release of Ma An Shan Ripe Pu-erh Tea 2016
We have just released Ma An Shan Ripe Pu-erh tea cake ( …
New Release of Tsukigase Asamomi Sencha 2017
We just released Tsukigase Asamomi Sencha as one of our …
New Release of Black Tie Guan Yin
We have released Black Tie Guan Yin. It is produced in …

PAGETOP