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Oxidation makes tea black

136 pointsby cmogni1about 3 years ago

14 comments

hinkleyabout 3 years ago
I stumbled into a presentation on tea at a tea festival a number of years ago. I keep meaning to figure out which notebook my notes are in and make copies because it was so good. The presenter was this elderly British gent with a background in operations who got sent out to figure out how to boost tea output.<p>There were a bunch of charts about time and temperature and humidity for various types of tea but the biggest fact was slightly buried. &#x27;fermentation&#x27; with respect to tea is a bit of a euphemism. It&#x27;s actually autolysis. The big epiphany moment for me was connecting the dots and seeing why that was the case. Caffeine is an insecticide. It&#x27;s stored in little crystals in the tissue. With oxalic acid, the crystals are the point. They&#x27;re sharp and they damage the attacker.<p>With caffeine it&#x27;s metabolic disruption. Within other organelles in the tea leaf are enzymes that can decompose the caffeine crystals into a solluble form. These chemicals only mix when the leaf is bruised, or masticated. They are booby trapped.<p>When you process <i>camellia sinensis</i> into tea, the oldest process is matcha, which started in China and is now mostly preserved in Japan, is drying the leaves and then powdering them, which I presume frees up some of the caffeine simply by mechanical decomposition. For the others the leaves are processed by bruising, heating and drying the leaves, and the order and duration dictates which kind of tea you get, and how much of the caffeine has been converted to a form that is water soluble. Black tea is aged longer, and has more available caffeine.<p>Almost none of them are actually fermented as in beer (puehr is the most notable, and the common reaction upon smelling it is, &quot;This reminds me of my grandmother&#x27;s garden.&quot; It is an acquired taste.) Edit: and kombucha, which is fermented after being steeped, rather than before. Also by many accounts an acquired taste.
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timonokoabout 3 years ago
I was sort of suffering from colored tooths (teeth?) problem. Meaning every time I took selfie I suffered about 5 seconds. The bloody dentist suggested monthly visits to the bloody dental hygienists.<p>Strange thing happened: I was flying my kite for kite aerial photography and a chinese ((or taiwanese) or japanese) tourist noted my blackened teeth an told that green tea does not color. And it worked ok. Even the cheapest Lidl tea works ok. I bit of acquired taste, but you will learn to love it.
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chasilabout 3 years ago
I had always understood that white tea had minimal processing, so I don&#x27;t understand this assertion:<p>&quot;Without oxidation, tea would taste unbearably bitter.&quot;<p>Perhaps white tea has not reached an adult phase with the associated bitterness.<p>Contast to:<p>&quot;White tea may refer to... minimally processed leaves of the Camellia sinensis plant.&quot;<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;White_tea" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;White_tea</a>
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aradox66about 3 years ago
The website is new, but this business also runs one of my favorite brick and mortar tea shops! It&#x27;s in the Oakland hills.<p>They pile up the steaming leaves from every cup they brew and the shop fills with the earthy caramel aroma of good tea.
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Teracotageabout 3 years ago
How about manipulating Oxidation of your tea cup? I add a squeeze of lemon and the tea lightens up in color, and it lasts longer before it tastes stale. In addition to lemon, I would add either cardamom,or cinnamon, or event mint leaves, and the over-oxidation that would make my cup of tea go stale will be delayed. I am that lazy tea drinker who is OD&#x27;ing on tea&#x2F;j.
prophesiabout 3 years ago
&quot;Contrary to popular belief, Red teas like Darjeeling actually have less caffeine than White or Green teas because they are so highly processed.&quot;<p>Is this actually true? I&#x27;ve never heard of green tea having more caffeine than red tea, besides maybe gunpowder green tea, which retains more caffeine due to less breakage from being rolled up.
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lambicabout 3 years ago
Can anyone explain this sentence: &quot;Because tannins weigh more than catechins, they do not taste bitter.&quot;
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noufalibrahimabout 3 years ago
An interesting colour change I&#x27;ve noticed it when you squeeze lemon into dark (almost black) tea. It lightens up a lot and becomes a pale brown. I&#x27;m not sure what but there is some chemical change going on there.
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blacksmith_tbabout 3 years ago
This is a pretty thorough intro to (mostly) Chinese tea, which seems fair to me since tea originated in China. Though I can see a few details to quibble over (e.g., some Taiwanese oolongs are barely oxidized, ~5% for Baozhongs sometimes[1]). Personally as much as I like white, green, and black teas, I think oolongs have the most variation, since they can have a mix of the characteristics of the other types. But I drink plenty of them all.<p>1: <a href="https:&#x2F;&#x2F;teadb.org&#x2F;baozhong&#x2F;" rel="nofollow">https:&#x2F;&#x2F;teadb.org&#x2F;baozhong&#x2F;</a>
hbarkaabout 3 years ago
The other dark tea, the fermented tea they mention in this article aka <i>hei cha</i> or commonly referred to as pu’er, scares me because there are bad quality versions of it containing mold due to their fermentation process. Hard to detect since it’s also a kind of black tea.
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ameliusabout 3 years ago
Tangential. Has anyone tried Tulsi tea? I recently did and got a bad experience from it. I think it has some psychoactive substance in it.
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mproudabout 3 years ago
How can you tell if a tea is oxidized or not?<p>Darker, black tea is more oxidized, and because it is, it has a larger flavor profile, as opposed to the bitter, less oxidized Green tea.<p>Thanks for coming to my TED talk.
hammockabout 3 years ago
Most things that are black are oxidized
m0lluskabout 3 years ago
black teas matter
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