Something I've noticed about greens

I have noticed this for a while now but never thought to comment on it. When I brew a green, when it's still hot/warm, the liquor is still whatever it's fresh-brewed original color was (light green or blue-green or whatever) but as the liquor cools off, it turns to more of a brown or a straw color. It's really interesting. I can tell my tea is cooled off by the color.

Melinda

Reply to
Melinda
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This is due to chemical oxidation of the green tea catechins into orange theaflavin - while the tea is sitting in your cup it reacts with oxygen dissoved in the water - same reaction as would happen to make black tea in a tea factory except that then it is catalysed by natural tea enzymes. Some green teas do this more than others: I suspect that using freshly drawn water also increases the rate of browning.

Nigel at Teacraft

Reply to
Nigel

snipped-for-privacy@corp.supernews.com7/7/05 00: snipped-for-privacy@yahoo.com

Melinda,

I would go further and guess that the color change indicates that little bits of stuff is floating around, continuing to brew, and ruining the taste as well as the color of your green tea. This sometimes cannot be helped. those bits are small enough to be unstrainable.

Michael

Reply to
Michael Plant

That's very interesting Nigel...does that mean, do you suppose, that when drinking green tea for it's health benefits, it would be better to drink it while it is still hot? I don't know if the catechins are better for one's health than the theaflavin...both are antioxidants aren't they?

Thanks for the info!

Melinda

Reply to
Melinda

That's also possible Michael, but if I overbrew my greens in hot water it still doesn't turn brown until it cools. You're right about the fine bits though...I get a lot of the fine hairs from the leaf surface in my tea but I figure that's a good thing. I don't actually deliberately wait until my tea is cold to drink it, but sometimes it gets forgotten. Unless I'm making iced green tea that is. It goes without saying that hot green tea and green tea that's been forgotten and left to cool taste different...I definitely don't get the depth of flavor with the cooled-off tea.

Melinda

Reply to
Melinda

What greens are we talking about? As a rule, I let my Japanese greens cool down a minute or so after brewing before consuming. Even though brewed at temps in the 160F range, this heat still can overwhelm the delicacy of the tea if drunk immediately after pouring in the cup.

--crymad

Reply to
crymad

Sometimes I'll make a small pot of green and keep it on my desk on a little holder with a tealight candle underneath to keep it warm. If any tea stays in the pot longer than about an hour, the same thing happens - it turns darker and the taste changes markedly. I'm not sure if this effect is a function of cooling or something else......................................p*

Reply to
pilo_

Hmm, this is something I haven't noticed myself. Maybe I just don't pay close enough attention, but could you describe how you make green tea?

/Lew

Reply to
Lewis Perin

So hot water can substitute for the enzymes destroyed by the firing of green tea?

/Lew

Reply to
Lewis Perin

While I haven't noticed a color change as the cup cools, I have often found that green tea liquor loses astringency and gains sweetness as it cools. Could this be a catechin->theaflavin effect?

/Lew

Reply to
Lewis Perin

Melinda,

I've noticed something similar, but it usually takes hours. I will occasionally make a pot of green tea in the afternoon at work; I drink the first infusion that afternoon, then make a second infusion and leave it till the next morning. Even after reheating it in a microwave I notice that the color usually has darkened and the flavor has changed. In some cases it seems more "oolong-like", and I attributed the change to slow oxidation overnight.

Some teas seem to benefit from this treatment - I've had Darjeelings that I thought improved the second day. Others, like very fresh greens, seem to lose their brightness (no surprise, I guess). Most black teas seem to show little discernable change, which favors the slow-oxidation theory.

Regards, Dean

Reply to
DPM

I have been told by my 'supplier' that you should soak green tea in a small quantity of cold/lukewarm water for a short while before adding boiling water. It would prevent the bitterness some greens have.

Wouter

Reply to
WJ van den Berg

I am referring to sencha but mostly to the various Chinese greens that I've been drinking (Kaihua Long Ding, Long Jing, etc.) And when I say "cool down" I mean room temp...I've left the glass for probably a good 30 minutes or longer.

As far as the delicacy for Japanese greens goes, I'm afraid my experience and tastes don't favor those (though I do drink them) so I could easily be missing subtlety there. I usually drink genmai cha if I'm going to drink a Japanese green. But if I do recall correctly I've seen that turn browner as it cools as well.

People can try this at home! (how's that for a switch...) brew a glass of green tea of your choice and note the color and then let it sit for a couple of hours and then take a look. But look at it in a clear glass.

Melinda

Reply to
Melinda

I may do a standard steep (4 grams in 300 ml of water at say 155-165 for about 45 sec the first time...depends on the tea). But I also at times do multiple successive steeps and pour them off into a larger glass pot which will go to my desk with me.

in order to see this it is important to use glass.

Also, good point from pilo...I have assumed it was from cooling because I don't use a tea light and all my tea cools off...I just assumed it was because of the lowering of temp. It could be a function of time for all I know though. I don't reheat my greens in the microwave, though I don't know what difference that would make if the change had already occured. Unless the change were a result of something "precipitating" out as the tea cooled which would go back into solution presumably when the tea was reheated.

Melinda

Reply to
Melinda

I've noticed this with blacks too. Especially yunnan gold. I'll be distracted half way through a pot, and when I come back an hour or so later, and the dark amber will have changed to almost coffee black. Marlene

Reply to
Marlene Wood

There is lots of fine particulate in this tea that escapes straining and continues brewing in this cup. Not only does the cup color change but also the taste. I opened a bag a couple of months ago and almost choked from the dust. Swirl in a glass pot and you'll see the residue almost like tiny soap bubbles on the sides. You'll see the bubbles as you empty the cup. You see this phenomena in the occasional British blend but not this apparent. I describe the taste as smoky vanilla and I've heard of only one other strain of tea off the coast of Africa with a natural vanilla taste without additives. I think this is a sine non qua tea from China. I think the taste would fool most coffee and tea drinkers.

Jim

Marlene Wood wrote:

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Space Cowboy

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