TeaChat

I haven't been able to find any information about this in other posts, so I thought I would start a new one.

Is it the tannin in tea leaves that cause brewed tea to be of different colors? And if so, are these tannins a natural byproduct of certain leaf types, or does it depend on the way the tea leaves are processed? For example, I just brewed a tieguanyin and and dong ding side-by-side. The resulting brew of the dong ding is much lighter than that of the tieguanyin even though they both seem to have been processed in similar ways.

One reason why I am asking is because I seem to get strong headaches whenever I drink tea with high tannin levels. Teas like DHP and tieguanyin seem to trigger such headaches while "lighter" (less tannic?) teas, like dong ding or dancong, do not.

Teas that are roasted will produce deeper colors than 'green' oolongs. Oxidation and fermentation will also play a part in color depth. I am not aware of tannins being the cause of color change but maybe I'm wrong.

With TGY, you have different levels of roasting. With some experience, you can look at the leaves and tell which have been roasted more than others.

The colour mostly has to do with two things....how much the tea is oxidized and how much the tea is roasted.

Oxidation is the process that turns an apple brown when you cut it...a very similar thing happens to tea leaves when they´re bruised. Oolongs and black teas are rubbed to bruise the leaves and begin the oxidation process...that´s where their colour comes from. Application of heat stops the enzymes responsible for the rapid oxidation by breaking them down...that´s how the level of oxidation can be controlled in oolongs.

The other thing is roasting...which is just what it sounds like...the leaves are roasted...often over charcoal fires this will alter the flavours and make the leaves (and the resulting infusion) darker...and also reduce the moisture content of the leaves (good for increasing shelf life)

There´s no actual tannic acid in tea...there are catechins which are considered pseudo-tannins but they´re abundant in all types of tea afaik.

As to the headaches...I really don´t know why one type of oolong could cause them and another not.

Thank you, Tead Off and Entropyembrace, for your helpful comments. I've read hundreds of both of your posts here in teachat and have learned a lot thanks to your useful information.

Actually, Tead Off, I just bought some 97/98 roasted TG today at Cha Yuen Fong here in Hong Kong. TokyoB told me that someone he knows highly recommends it. It only just occurred to me that it must have been you!

entropyembrace wrote: As to the headaches...I really don´t know why one type of oolong could cause them and another not.

A lot of people get headaches from light TGY. I've have had some from bad TGY and some from bad Dong Ding.

santunoo wrote:Thank you, Tead Off and Entropyembrace, for your helpful comments. I've read hundreds of both of your posts here in teachat and have learned a lot thanks to your useful information.

Actually, Tead Off, I just bought some 97/98 roasted TG today at Cha Yuen Fong here in Hong Kong. TokyoB told me that someone he knows highly recommends it. It only just occurred to me that it must have been you!

Ah, you must be his cousin in Hong Kong. Did you ask for the discount?
Let me know how you like it. I just drank some of it this evening. My wife also gives it a thumbs up. She is a bigger critic than I. Can you imagine?

Ah, you must be his cousin in Hong Kong. Did you ask for the discount?
Let me know how you like it. I just drank some of it this evening. My wife also gives it a thumbs up. She is a bigger critic than I. Can you imagine? [/quote]

Yep! That's me. The owners were such nice people. I sat there for 2 hours chatting with them about all things tea related. And yes, they did give me a nice discount The organic TG is unlike other TG's I've tasted. Although it's not as sweet as regular TG, the taste profile is much fuller.

I'm going back today to watch them charcoal roast some tea and to buy a smaller gaiwan. Let me know when you next come to HK, and we can go do some tea tasting!

santunoo wrote:Ah, you must be his cousin in Hong Kong. Did you ask for the discount?
Let me know how you like it. I just drank some of it this evening. My wife also gives it a thumbs up. She is a bigger critic than I. Can you imagine?

Yep! That's me. The owners were such nice people. I sat there for 2 hours chatting with them about all things tea related. And yes, they did give me a nice discount The organic TG is unlike other TG's I've tasted. Although it's not as sweet as regular TG, the taste profile is much fuller.

I'm going back today to watch them charcoal roast some tea and to buy a smaller gaiwan. Let me know when you next come to HK, and we can go do some tea tasting![/quote]

Yes, very nice people. I like the mother quite a lot. Watching the father roast should be an interesting experience. I forgot that they told me the aged TGY is also organic. They also told me that before 2000, none of the farmers used pesticides where their farm is. They couldn't get any locally. Now, everyone uses them.

I also bought a small 60ml gaiwan that I use for certain teas, mainly to taste when I am alone. Save some of that tea for TokyoB! I'll let you know when I come to HK again.

Hum maybe this is a complex question with many varibles....

according to this site http://www.fmltea.com/Teainfo/tea-chemistry%20.htm

(also check out links page, Victoria and people who appreciate english style teawares and shiny fine things may enjoy http://www.theteapotshoppe.com/index.html which is also under the green tea links)

Biochemical compounds responsible for colour...

Compounds
Theaflavins = Yellowish brown
Thearubigins = Reddish brown
Flavonol glycosides = Light yellow
Pheophorbide = Brownish
Pheophytin = Blackish
Carotene = Yellow

I also think water plays a role in the colour and intensity that a brew comes out, it seems the higher the pH the quicker a brew will darken when brewing and when letting sit for a while.

And then there is roasting and oxidation like others have mentioned. Maybe mineral composition of water also is a variable. I am betting like many things in tea its complicated