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Oxidation makes tea black

sophiescuppatea.com

31–40 of 79 posts

Re: Oxidation makes tea black

#31
post #3

The website is new, but this business also runs one of my favorite brick and mortar tea shops! It's in the Oakland hills. They pile up the steaming leaves from every cup they brew and the shop fills with the earthy caramel aroma of good tea.

ditto, one of the best stores i know of

Re: Oxidation makes tea black

#32
post #2

I had always understood that white tea had minimal processing, so I don't understand this assertion: "Without oxidation, tea would taste unbearably bitter." Perhaps white tea has not reached an adult phase with the associated bitterness. Contast to: "White tea may refer to... minimally processed leaves of the Camellia sinensis plant." https://en.wikipedia.org/wiki/White_tea

Traditionally white tea was created from tea buds. If you've ever gardened, you know how dicey those first few days are because the plants that have defenses against caterpillars and slugs are vulnerable until the leaves are fully formed. Caffeine is a pesticide, and the young shoots don't contain much of it. Last I remembered looking, white tea has about the same caffeine as decaffeinated coffee (which I use both as a sales pitch for getting people to try white tea and a warning against people complaining about having trouble sleeping - there's still caffeine in your decaf, buddy).

Since you pick the leaves before they are grown, you're pruning the tree and potentially reducing your crop. Which is why it was a drink of the nobility. Basically you're so rich you can afford to reduce your crop by (conjecture) 10% for a taste sensation, or pay someone else for the privilege.

I suspect we have so much of it now because 1) Republic of Tea basically went through every tea fad in the history of tea in a 15 year period, presumably to keep sales numbers up with novelty, and 2) it's likely that there is oversupply in the tea market, so white tea gives you another shot at a sale.

Unlike coffee, which gets one harvest per year (although some people are trying to bring coffee leaf tea into the group consciousness), it's typical to get at least 2 harvests of tea per year, 3 or more in a great year. Which I discovered when I noticed my dealer putting numbers and/or seasons on her tea. If they are regrowing that fast then white tea might not be that big of a burden.

Re: Oxidation makes tea black

#33
post #19
post #6

Earlier quoted context omitted.

White tea is oxidized naturally for a while. The article is referring to freshly picked leaves.

The odd thing is that the range (and top end) of antioxidants in white tea is larger than in green. "Total catechin content (TCC) for white teas ranged widely from 14.40 to 369.60 mg/g of dry plant material for water extracts and 47.16 to 163.94 mg/g for methanol extracts. TCC for green teas also ranged more than 10-fold, from 21.38 to 228.20 mg/g of dry plant material for water extracts and 32.23 to 141.24 mg/g for…

Is it odd or is it thermal breakdown of chemicals?

Re: Oxidation makes tea black

#34
post #6

Earlier quoted context omitted.

White tea is oxidized naturally for a while. The article is referring to freshly picked leaves.

That would be green tea no? You pick the green tea, cook it to denature the enzymes to arrest the oxidization (called the "killgreen" step in Chinese) and voila, green tea! Lots of green teas can be quite smooth and even more so with more careful brewing.

The Brit I mentioned elsewhere seemed to think it was the drying that arrested the chemical processes in the tea.

He was also adamant about storing it in well sealed containers out of direct sunlight. I ended up throwing away a couple of containers because of this (although I've kept a couple that are just too beautiful to part with - I store my daily drinker in there since it doesn't need to keep as long). Also explains why my dealer uses mylar vacuum packs for anything over an ounce. No oxygen, no light.

Re: Oxidation makes tea black

#35

"Contrary to popular belief, Red teas like Darjeeling actually have less caffeine than White or Green teas because they are so highly processed." Is this actually true? I'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.

My suspicion here is that black tea, especially when prepared in the British style, has more caffeine per cup because it's brewed to be much stronger than green teas typically are. So both can be true, black tea typically has more caffeine per cup, but black tea leaves have less caffeine than green tea leaves when compared by weight or volume.

Re: Oxidation makes tea black

#36
post #15
post #10

Can anyone explain this sentence: "Because tannins weigh more than catechins, they do not taste bitter."

Higher weight polyphenols tend to taste less bitter than lower weight ones. Its more correlation than causation because I don’t think we precisely know why this is.

I wonder if they're talking about the blurred lines between taste and smell. Most of what we 'taste' is happening in our nose.

Turns out the French and Italians with all of their fancy wine glasses for different kinds of wine are not insane. Glass shape effects the timing of scent versus taste, and so lighter wines have a narrower glass to shorten the time. The heavier the red the wider the glass.

Re: Oxidation makes tea black

#37
post #27

The other dark tea, the fermented tea they mention in this article aka hei cha 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.

It's not a black tea, at least in the western sense. Our black tea is actually called hong cha in Chinese, which means red tea. They're simply different types of tea.

There are also two different style pf pu'ers which have little to do with each other. The style you're talking about is shu pu'er, which is deliberately piled and made wet in order to trigger a sped up fermentation process. This is opposed to sheng pu'er, which is processed into bricks from very young, raw leaves called maocha, and is then aged for a number of years before it is drank. This results in a much slower and subtler fermentation process. The taste of shu and sheng are quite different.

I've never personally had an encounter with a bad batch of either shu or sheng pu'er, but the shu variant is more prone to this due to the process.

It's notable that pu'er is steeped at a (close to) 100 degrees celsius and the first one or two short steepings are discarded. This is to kill and wash off any microorganisms or dirt that may be present.

Re: Oxidation makes tea black

#38
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'ing on tea/j.

Re: Oxidation makes tea black

#39
post #3

The website is new, but this business also runs one of my favorite brick and mortar tea shops! It's in the Oakland hills. They pile up the steaming leaves from every cup they brew and the shop fills with the earthy caramel aroma of good tea.

May just be the prices on their website, but they strike me as being quite expensive. They also use anglicized names with very little information about the tea, so it's hard to know what you're buying.

Re: Oxidation makes tea black

#40
post #23

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. There were a bunch of charts about time and temperature and humidity for various types of tea but the biggest…

That's a very good description of the enzymatic process in tea.

Regarding "oldest process" though, I'm not sure which is the earliest processing method for tea but compressed tea / tea bricks as Pu-erh (although compressed tea ≠ Pu-erh) is attributed to Tang dynasty (AD 618-907) and it precedes Matcha which is attributed to the Song dynasty period (960–1279).

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