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Tea (rec.drink.tea) Discussion relating to tea, the world's second most consumed beverage (after water), made by infusing or boiling the leaves of the tea plant (C. sinensis or close relatives) in water. |
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I saw it mentioned in a post today but I can't find the thread now. I've
never heard of it before and would appreciate it if someone could explain it. Giselle (new to this but just found a green tea I love) |
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"Volfie "Scary Poppins" Jackson" > wrote:
> I saw it mentioned in a post today but I can't find the thread now. I've > never heard of it before and would appreciate it if someone could explain > it. Essentially a white is like a very delicate green. Whites undergo the least processing of any kind of tea. They are made from young leaves that are just simply dried. -- Randy (if replying by e-mail, remove SPAMFREE from my address) |
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While intrepidly exploring rec.food.drink.tea, RJP rolled
initiative and posted the following: > "Volfie "Scary Poppins" Jackson" > wrote: > >> I saw it mentioned in a post today but I can't find the thread >> now. I've never heard of it before and would appreciate it if >> someone could explain it. > > Essentially a white is like a very delicate green. Whites > undergo the least processing of any kind of tea. They are made > from young leaves that are just simply dried. And, as such, are even more sensitive to heat. My Peony Blanc gets steeped at a lower temp than my greens and for about twice as long. It is, however, a very soothing final product and makes an absolutely WONDERFUL iced tea on a hot summer day. -- Derek Leaders are like eagles. We don't have either of them here. |
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On Fri, 05 Mar 2004 14:56:53 -0800, Volfie \Scary Poppins\ Jackson wrote:
> I saw it mentioned in a post today but I can't find the thread now. I've > never heard of it before and would appreciate it if someone could > explain it. > > Giselle (new to this but just found a green tea I love) It's been my understanding that white tea is basically a green tea with white down (fuzz) on the leaves. I've heard it said that white tea has a mildly depressant quality, more than being a stimulant. White teas tend to have a lighter taste than green teas, which in turn tend to be lighter than oolongs or blacks. |
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"Volfie \"Scary Poppins\" Jackson" > writes:
> I saw it mentioned in a post today but I can't find the thread now. I've > never heard of it before and would appreciate it if someone could explain > it. > > Giselle (new to this but just found a green tea I love) You should read the excellent FAQ for this group http://www.faqs.org/faqs/drink/tea/faq/ This is not the tea FAQ's home page, but contains a copy of the FAQ, along with many other FAQs and is an excellent site worth knowing about. It has a link to the homepage, by Chistopher Roberson's, which has other useful tea links. Cheers, - Joel |
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Bromo > writes:
> On 3/5/04 11:41 PM, in article > , "Dan Stromberg" > > wrote: > > > I've heard it said that white tea has a mildly depressant quality, more > > than being a stimulant. > > It does not have very much caffeine in it at all This is a MYTH! There is nothing in the way the other kinds of tea are processed that could *introduce* caffeine. If anything, it might break it down, but that doesn't happen either. Holy Mountain Trading Company has an analysis of some of their teas, and you'll see the white tea is right up there for caffeine content. http://www.holymtn.com/tea/teacaffeine.htm Cheers, - Joel |
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![]() Thanks for all the help and explanations, everyone! Giselle (adding white tea to my next tea shopping list) |
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"Joel Reicher" > wrote in message
... > > > I've heard it said that white tea has a mildly depressant quality, more > > > than being a stimulant. > > > > It does not have very much caffeine in it at all > > This is a MYTH! There is nothing in the way the other kinds of tea are > processed that could *introduce* caffeine. If anything, it might break > it down, but that doesn't happen either. I guess that's true enough, but white tea is usually made from buds, and it is possible that the caffeine content in buds is lower than in leaves. |
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On 3/7/04 1:19 PM, in article , "Jon
Nossen" > wrote: > "Joel Reicher" > wrote in message > ... >>>> I've heard it said that white tea has a mildly depressant > quality, more >>>> than being a stimulant. >>> >>> It does not have very much caffeine in it at all >> >> This is a MYTH! There is nothing in the way the other kinds of > tea are >> processed that could *introduce* caffeine. If anything, it > might break >> it down, but that doesn't happen either. > > I guess that's true enough, but white tea is usually made from > buds, and it is possible that the caffeine content in buds is > lower than in leaves. I just looked it up - she is right - caffeine levels in tea is roughly the same, though actual levels will depend upon steeping time. |
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"Jon Nossen" > writes:
> "Joel Reicher" > wrote in message > ... > > > > I've heard it said that white tea has a mildly depressant > > > > quality, more than being a stimulant. > > > > > > It does not have very much caffeine in it at all > > > > This is a MYTH! There is nothing in the way the other kinds of tea > > are processed that could *introduce* caffeine. If anything, it > > might break it down, but that doesn't happen either. > > I guess that's true enough, but white tea is usually made from > buds, No, it's *sometimes* made from buds. Silver Needles/Yinzhen yes, White Peony/Bai Mudan/Pai Mutan no, Shou Mei no, etc. Some greens, by the way, are bud-only. > and it is possible that the caffeine content in buds is lower than > in leaves. I don't think so, based on the small collection of numbers on the Holy Mtn caffeine content page. /Lew --- Lew Perin / http://www.panix.com/~perin/babelcarp.html |
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"Lewis Perin" > wrote in message
news ![]() > > I guess that's true enough, but white tea is usually made from > > buds, > > No, it's *sometimes* made from buds. Silver Needles/Yinzhen yes, > White Peony/Bai Mudan/Pai Mutan no, Shou Mei no, etc. Some greens, by > the way, are bud-only. I thought the "lower quality" white teas like Baimudan was made from buds *and* the first and/or second leaf of the stem. Are you saying that is wrong? > > and it is possible that the caffeine content in buds is lower than > > in leaves. > > I don't think so, based on the small collection of numbers on the Holy > Mtn caffeine content page. I'm not sure if that is a reliable source. Don't they state that the teas they tested were made from tea bags? *Tea bags of white tea*? |
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"Jon Nossen" > writes:
> "Lewis Perin" > wrote in message > news ![]() > > > I guess that's true enough, but white tea is usually made from > > > buds, > > > > No, it's *sometimes* made from buds. Silver Needles/Yinzhen yes, > > White Peony/Bai Mudan/Pai Mutan no, Shou Mei no, etc. Some > > greens, by the way, are bud-only. > > I thought the "lower quality" white teas like Baimudan was made > from buds *and* the first and/or second leaf of the stem. Are > you saying that is wrong? I'm saying buds in Bai Mudan are very rare experience. > > > and it is possible that the caffeine content in buds is lower > > > than in leaves. > > > > I don't think so, based on the small collection of numbers on the > > Holy Mtn caffeine content page. > > I'm not sure if that is a reliable source. Don't they state that > the teas they tested were made from tea bags? *Tea bags of white > tea*? I'm unable to cerify those numbers independently, but I don't see any reason to doubt them. I believe in tea-leaf freedom as much as anyone, but I don't see why incarceration would invalidate the caffeine figures. /Lew --- Lew Perin / http://www.panix.com/~perin/babelcarp.html |
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"Lewis Perin" > wrote in message
news ![]() > > > > and it is possible that the caffeine content in buds is lower > > > > than in leaves. > > > > > > I don't think so, based on the small collection of numbers on the > > > Holy Mtn caffeine content page. > > > > I'm not sure if that is a reliable source. Don't they state that > > the teas they tested were made from tea bags? *Tea bags of white > > tea*? > > I'm unable to cerify those numbers independently, but I don't see any > reason to doubt them. I believe in tea-leaf freedom as much as > anyone, but I don't see why incarceration would invalidate the > caffeine figures. Do tea bags with white tea actually exist? Seems like a very strange animal to me. According to the site, "The finely ground tea was extracted with hot water." So is the amount of caffeine in white tea consisting of *whole leaves or buds* similar to the amount in *finely ground* tea? Just wondering. |
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Jon /9/04
> "Lewis Perin" > wrote in message > news ![]() >>>>> and it is possible that the caffeine content in buds is > lower >>>>> than in leaves. >>>> >>>> I don't think so, based on the small collection of numbers > on the >>>> Holy Mtn caffeine content page. >>> >>> I'm not sure if that is a reliable source. Don't they state > that >>> the teas they tested were made from tea bags? *Tea bags of > white >>> tea*? >> >> I'm unable to cerify those numbers independently, but I don't > see any >> reason to doubt them. I believe in tea-leaf freedom as much > as >> anyone, but I don't see why incarceration would invalidate the >> caffeine figures. > > Do tea bags with white tea actually exist? Seems like a very > strange animal to me. > > According to the site, "The finely ground tea was extracted with > hot water." > > So is the amount of caffeine in white tea consisting of *whole > leaves or buds* similar to the amount in *finely ground* tea? > Just wondering. > > Jon, I think consistency is the key here; we are getting an accurate reading of *relative* amounts of caffeine from tea to tea, but not the specific amount you might expect from *your" cup of tea. What we might be able to deduce from the tables is that one tea has more caffeine than another, all other things being equal. I'm highly skeptical about these tables and their value anyway, having nowhere near the faith that Lew has. Regarding caffeine in tea, I just keep asking until I get the answers I want. Then I stop. Michael |
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"Jon Nossen" > writes:
> "Lewis Perin" > wrote in message > news ![]() > > > > > and it is possible that the caffeine content in buds is > > > > > lower than in leaves. > > > > > > > > I don't think so, based on the small collection of numbers on > > > > the Holy Mtn caffeine content page. > > > > > > I'm not sure if that is a reliable source. Don't they state that > > > the teas they tested were made from tea bags? *Tea bags of white > > > tea*? > > > > I'm unable to cerify those numbers independently, but I don't see > > any reason to doubt them. I believe in tea-leaf freedom as much > > as anyone, but I don't see why incarceration would invalidate the > > caffeine figures. > > Do tea bags with white tea actually exist? Seems like a very > strange animal to me. Come to think about it, why are we worrying about tea bags? It looks as if the teas whose caffeine content is listed on that Holy Mtn page are all loose leaf (or Puerh tuocha etc.) teas from Holy Mtn. > According to the site, "The finely ground tea was extracted with > hot water." The way I read this is, they ground up the leaves before doing the caffeine measurements. > So is the amount of caffeine in white tea consisting of *whole > leaves or buds* similar to the amount in *finely ground* tea? > Just wondering. Unless the grinding adds or subtracts caffeine, both of which seem rather unlikely to me. /Lew --- Lew Perin / http://www.panix.com/~perin/babelcarp.html |
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On Tue, 09 Mar 2004 12:25:23 -0800, Lewis Perin wrote:
> "Jon Nossen" > writes: > >> "Lewis Perin" > wrote in message >> news ![]() >> > > > > and it is possible that the caffeine content in buds is lower >> > > > > than in leaves. >> > > > >> > > > I don't think so, based on the small collection of numbers on the >> > > > Holy Mtn caffeine content page. >> > > >> > > I'm not sure if that is a reliable source. Don't they state that >> > > the teas they tested were made from tea bags? *Tea bags of white >> > > tea*? >> > >> > I'm unable to cerify those numbers independently, but I don't see any >> > reason to doubt them. I believe in tea-leaf freedom as much as >> > anyone, but I don't see why incarceration would invalidate the >> > caffeine figures. >> >> Do tea bags with white tea actually exist? Seems like a very strange >> animal to me. > > Come to think about it, why are we worrying about tea bags? It looks as > if the teas whose caffeine content is listed on that Holy Mtn page are > all loose leaf (or Puerh tuocha etc.) teas from Holy Mtn. > >> According to the site, "The finely ground tea was extracted with hot >> water." > > The way I read this is, they ground up the leaves before doing the > caffeine measurements. > >> So is the amount of caffeine in white tea consisting of *whole leaves >> or buds* similar to the amount in *finely ground* tea? Just wondering. > > Unless the grinding adds or subtracts caffeine, both of which seem > rather unlikely to me. Is matcha ground up? The one used in the Japanese tea ceremony? |
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Dan Stromberg > writes:
> [...caffeine tests, tea bags, white tea, grinding leaves...] > Is matcha ground up? The one used in the Japanese tea ceremony? Yes. /Lew --- Lew Perin / http://www.panix.com/~perin/babelcarp.html |
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"Jon Nossen" > writes:
> [...bags, grinding, and caffeine...] > > > > So is the amount of caffeine in white tea consisting of *whole > > > leaves or buds* similar to the amount in *finely ground* tea? > > > Just wondering. > > > > Unless the grinding adds or subtracts caffeine, both of which seem > > rather unlikely to me. > > Not quite. The grinding makes sure that *all* the caffeine in > the leaves is extracted, as with Matcha tea, instead of an > amount *somewhat less* than that - of course, how much less will > depend on the particle size of the tea before grinding, the > water temperature and the steeping time. > > Which is why I wonder how useful the stated caffeine amounts > really are. I think they're useful as long as we're clear on what they are and what they aren't. They *are* a standardized (loosely speaking) measurement of caffeine, applying the same measurement technique to all samples. That's the reason they ground up the leaves, I'm sure. They *aren't* a direct indication of how much caffeine gets into the cup when you brew 2.0 grams of each tea "the right way", because "the right way" will vary the temperature and steep time depending on the type of tea. Let's not even think about how many "right ways" there really are to brew a given type of tea! What would make these measurements a lot more useful would be some rules, however imprecise, for calculating caffeine uptake according to brew temperature and steep time. A year or two ago on RFDT there was an interesting thread ("Strong, Cheap, Black Tea") that made some progress on this, but I think temperature was ignored. Are you listening, Dog Ma? /Lew --- Lew Perin / http://www.panix.com/~perin/babelcarp.html |
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![]() > What would make these measurements a lot more useful would be some > rules, however imprecise, for calculating caffeine uptake according to > brew temperature and steep time. A year or two ago on RFDT there was > an interesting thread ("Strong, Cheap, Black Tea") that made some > progress on this, but I think temperature was ignored. > > Are you listening, Dog Ma? Urrgh - I'm gonna regret this. But so are you, most likely. OK, here's a chemist's take: 1. You're all correct. 1a. There are a lot of hidden variables here. E.g., the detailed history of leaf preparation, like CTC vs. wither/toast, probably has a major effect on the permeability of cell structures in the final product. If we consider that broken leaf (unlike dust) is still mostly face with relatively little edge, cell-wall permeability may matter a lotmore than sieve size. 2. That web site (like most) leaves out the most important datum any scientist would demand first: experimental conditions. Alkaloid-content measurements on everything from tea/coffee to opium and beyond have been SOP for over a century. Usual deal is to dry the leaves thoroughly (and, to pre-empt the question, these methylxanthine alkaloids are reasonably robust to heat and air), finely grind, and extract with a hydrophobic solvent like chloroform. Mixed alkaloids are then extracted into dilute aqueous acid, leaving other organics in the solvent. The aqueous solution is basified, alkaloids only (less sugars, tannins, etc.) re-extracted, usually into ether. For tea, what's left is fairly pure theophylline, which can be weighed up against starting leaf. If a precise number was needed, alkaloids could be separated by liquid chromatography or fractional crystallization. The foregoing is a few minutes' work in a going lab. (I know you didn't really care, but I've done A LOT of these. And it's hard to forget, try as one might; especially getting refused a coming-home kiss because of the ether stink on one's breath.) 3. Nowadays, however, it can all be done far more accurately about three minutes, with complete details of all the main soluble fractions, by high-performance liquid chromatography. 4. Given the economic value of tea, somebody must have done a decent study on this. However, as exemplified by an appallingly commercial and scientifically corrupt article on espresso in a recent issue of Scientific American, objectivity may be subverted. 5. There aren't all that many independent variables, as these things go. I suspect that major levers a - leaf size (e.g., whole, broken, fannings) - fermentation history (none, halfway oolong, all-black) - water temperature - water purity (a low concentration of some ions can drastically reduce solubility of organics, and possibly cell permeability as well) all, of course, as a function of steeping time. Naturally, different tea strains, parts, harvest times and plant maturities will all make a difference. The above would permit some generalizations for extraction rates of key flavor and physiology components for all teas. 6. That whole deal is about three days' work on equipment that's standard in all sorts of academic, industrial and scientific labs. That's if run as a full-factorial series, which no-one does anymore since experimental-design software has shown the True Way. It would therefore be a dandy science project for an advanced high-schooler or community college student. I'd have done it myself years ago, but I kind of enjoy the mystery. And now I'm out of the lab, so can't offer. 7. So back to (1) - who cares what the alkaloid or other bioactive/organoleptic content of a leaf is? We want to know how much comes out, and when, and how to get the personal best balance. And for that, the perennial recommendation of {try new things, find people of discrimination to recommend others, vary conditions to get the best from every tea} can't be beat. In a more or less unrelated note, since this post isn't yet long enough, has anyone ever heard of white tea made by etiolation? (That's light-starving plants to bleach them, as is done with asparagus.) Might be an interesting effect. Especially since, or so I assume, many of the things we like best about tea were put there by God and/or Darwin to keep animals from eating the leaves. -DM |
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"Dog Ma 1" (reply w/o spam)> writes:
> > What would make these measurements a lot more useful would be some > > rules, however imprecise, for calculating caffeine uptake according to > > brew temperature and steep time. A year or two ago on RFDT there was > > an interesting thread ("Strong, Cheap, Black Tea") that made some > > progress on this, but I think temperature was ignored. > > > > Are you listening, Dog Ma? > >[...how a chemist would measure, plus lots of factors in cup caffeine...] Thanks! That was instructive and interesting, but I should've made clear what I was hoping for: for a given tea, some kind of formula for caffeine extraction in 2 independent variables (temp and time.) The particularity of the individual type of tea would be represented, I suppose, by some constant (factors?) > In a more or less unrelated note, since this post isn't yet long enough, has > anyone ever heard of white tea made by etiolation? (That's light-starving > plants to bleach them, as is done with asparagus.) Might be an interesting > effect. Especially since, or so I assume, many of the things we like best > about tea were put there by God and/or Darwin to keep animals from eating > the leaves. Hmm, are you hoping for even more confusion as to the meaning of "white tea" than there already is out there?! Gyokuro is shaded for at least part of its life; I don't suppose that qualifies, does it? /Lew --- Lew Perin / http://www.panix.com/~perin/babelcarp.html |
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"Lewis Perin" > wrote:
> Thanks! That was instructive and interesting, but I should've made > clear what I was hoping for: for a given tea, some kind of formula for > caffeine extraction in 2 independent variables (temp and time.) The > particularity of the individual type of tea would be represented, I > suppose, by some constant (factors?) Right with you, bro. I've just never seen a comprehensive chart, table or algorithm of the type you describe. Would be nice to have, for sure. It may be that the leaf-processing and other variables I mentioned, or yet others, make generalization impossible. An earlier post to this NG or Teamail mentioned a "bell curve" for extraction of various substances. Actually, it's much more complicated than that. Whatever leaf is used, dissolution of surface exudates will be almost instantaneous; hence the rapid coloring from EBT. For leaf contents, inward diffusion of water and outward of solubles are highly non-linear, described by complex partial differential equations, because degree of hydration influences rate of further hydration. Then, over time, materials of lower solubility and those buried deeper in plant tissue will elute at an exponentially declining rate. So for any given material of interest, there may be a surge in solution rate, a dip, a slower rise, and a gradual fall-off. Every infusion will differ not only in total strength, but also in balance. There's plenty of published work on efficient extraction of valuable chemicals from plant matter, but that's usually a question of how close they can get to total extraction, how quickly and how cheaply. Sorry there's no simple answer, AFAIK. One almost-fact is that since the alkaloids are relatively soluble in even warmish water, most of the accessible theophylline and caffeine are probably out in a few seconds. I've fooled around with completely hydrating leaves in cold water before that first steep, and it seems to remove most of the caffeine (based on the observation that I don't get my usual tea jitters) with nil loss of flavor or color. > Hmm, are you hoping for even more confusion as to the meaning of > "white tea" than there already is out there?! Absolutely. After all, as one of my profs used to say at every possible occasion, erudition is not incontrovertibly predicated on obfuscation by nugatory sesquipedalianism. > Gyokuro is shaded for at least part of its life; I don't suppose that > qualifies, does it? Might well. My impression is that shade treatment of gyokuro is as much about lightening the colour as anything. But I'm a philistine with limited taste discrimination, so wouldn't know. I've never had a completely etiolated tea, e.g. where branches were put in black plastic as soon as leaves emerged. Seen this done for visual effect on greenhouse plants, and it might make a very different taste. Who knows a plantation owner who'll give it a try? -DM |
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Dog Ma /10/04
reply w/o spam [snipped passages from exchange between Lew and Dog Ma, sesquipedalian surely but hardly nugatory] >...most of the > accessible theophylline and caffeine are probably out in a few seconds. I've > fooled around with completely hydrating leaves in cold water before that > first steep, and it seems to remove most of the caffeine (based on the > observation that I don't get my usual tea jitters) with nil loss of flavor > or color. Happily read through the chemistry of this and especially your enlightening previous post. (Two aspirin were sufficient to clear my head, -- I'm just a poor country boy -- and so on we go.) Does my hoped for answer regarding caffeine and theophilline -- that the second steep contains little or none -- lie in the truth of your statements above? Is it really your considered opinion that a few seconds of steep is sufficient to remove said elements? Good news indeed. > >> Hmm, are you hoping for even more confusion as to the meaning of >> "white tea" than there already is out there?! > > Absolutely. After all, as one of my profs used to say at every possible > occasion, erudition is not incontrovertibly predicated on obfuscation by > nugatory sesquipedalianism. > >> Gyokuro is shaded for at least part of its life; I don't suppose that >> qualifies, does it? > > Might well. My impression is that shade treatment of gyokuro is as much > about lightening the colour as anything. But I'm a philistine with limited > taste discrimination, so wouldn't know. I've never had a completely > etiolated tea, e.g. where branches were put in black plastic as soon as > leaves emerged. Seen this done for visual effect on greenhouse plants, and > it might make a very different taste. Who knows a plantation owner who'll > give it a try? I wonder if Ito En might point us in the right direction. They seem to have a handle on these things. I think. Or maybe Nigel? Michael |
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"Michael Plant" > wrote
> Two aspirin were sufficient to clear my head > Does my hoped for answer regarding > caffeine and theophilline -- that the second steep contains little or none > -- lie in the truth of your statements above? Is it really your considered > opinion that a few seconds of steep is sufficient to remove said elements? Glad to have contributed to your cardiovascular health - all us mature people should take aspirin every day, as well as plenty of tea. It's frustrating, because I could answer the alkaloid question easily, quantatively and definitively for a whole range of teas and brewing types in about an hour - if I still worked in the lab! Caffeine/theophylline are about as easy to analyze as anything could be. (The other stuff is harder, partly because it's not all single, well-defined compounds, and partly because there's much less of it.) I'm going to hazard a guess that for most teas, a few minutes in tepid water will take out most of the alkaloids and not much else. That five seconds in hot water will take out 90% from anything. And that in fannings/dust and even small broken-leaf blacks, with most of the taste in dried surface exudates, only cold water will remove buzz w/o taking away too much flavor. That's an informed guess, because it's what I do. Too much caffeine just keeps me awake at night; I only have a cup every month or two, and have a low tolerance. Theophylline OD makes me quite ill. So if I'm having more than one mug of strong Assam or one pot of sencha, I'll wash out most of the theophylline per above. Cold water seems to work pretty well, though I have yet to try it on expensive oolongs. I'll ask around and see if anyone I know, or a student at the local technical college, will do an evening's HPLC analysis (I'd provide the samples) for the price of a sushi dinner - or perhaps a good gong-fu pot and an ounce of Dan Cong. -DM |
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Nice post, DM. Comments on two points:
Dog Ma 1 (reply w/o spam)> wrote: > 6. That whole deal is about three days' work on equipment that's standard in > all sorts of academic, industrial and scientific labs. That's if run as a > full-factorial series, which no-one does anymore since experimental-design > software has shown the True Way. It would therefore be a dandy science > project for an advanced high-schooler or community college student. I'd have > done it myself years ago, but I kind of enjoy the mystery. And now I'm out > of the lab, so can't offer. Hey, factorial designs are nice if you want to know about all combinations of conditions and types of tea. I presume that the goal of such an experiment would not be to maximize the yield of caffeine. > In a more or less unrelated note, since this post isn't yet long enough, has > anyone ever heard of white tea made by etiolation? (That's light-starving > plants to bleach them, as is done with asparagus.) Might be an interesting > effect. Especially since, or so I assume, many of the things we like best > about tea were put there by God and/or Darwin to keep animals from eating > the leaves. So that's what we Wisconsinites are - "etiolated". About this time of year we all develop a kind of tint between ivory and light green. The Japanese partially shade their Gyokuro, but that is to increase the amount of chlorophyll. I suppose that the effect is nonlinear, with a bit of shade making tea greener. Best, Rick. |
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"Dog Ma 1" (reply w/o spam)> wrote in
message ... > I'm going to hazard a guess that for most teas, a few minutes in tepid water > will take out most of the alkaloids and not much else. That five seconds in > hot water will take out 90% from anything. And that in fannings/dust and > even small broken-leaf blacks, with most of the taste in dried surface > exudates, only cold water will remove buzz w/o taking away too much flavor. FWIW, I once found a research article on the web, where they had analyzed how much of the main ingredients in tea bags were extracted after 2 minutes steeping time. The results we Caffeine: 55-90% Flavonols and flavones glucosides: 55-90% Flavanols (catechins), theaflavins and thearubigins: 35-55% I unfortunately don't have the time to try to find the reference or any more details, as in a few hours I will be heading for a plane to take me to the land of Ceylon tea... Sri Lanka. Will stay there for three weeks. Hopefully I will be able to visit a tea plantation in the Nuwara Eliya district. |
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On Thu, 11 Mar 2004 02:25:07 GMT, "Dog Ma 1"
(reply w/o spam)> cast caution to the wind and posted: >Sorry there's no simple answer, AFAIK. One almost-fact is that since the >alkaloids are relatively soluble in even warmish water, most of the >accessible theophylline and caffeine are probably out in a few seconds. I've >fooled around with completely hydrating leaves in cold water before that >first steep, and it seems to remove most of the caffeine (based on the >observation that I don't get my usual tea jitters) with nil loss of flavor >or color. So, does this mean that most puerh is basically caffeine free, considering that most preparation methods call for a rinse first? Mike |
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"Dog Ma 1" (reply w/o spam)> writes:
> [...caffeine and steeping...] > > I'm going to hazard a guess that for most teas, a few minutes in tepid water > will take out most of the alkaloids and not much else. That five seconds in > hot water will take out 90% from anything. And that in fannings/dust and > even small broken-leaf blacks, with most of the taste in dried surface > exudates, only cold water will remove buzz w/o taking away too much flavor. I've just been trying to find some data on caffeine's extraction from tea leaves as a function of steep temperature and time. (Using the lazy man's research tool: Google.) Regarding temperature, there's lots of talk about how lower steep temperatures slow down the extraction, but not numbers. A Canadian university student health pamphlet http://www-health.concordia.ca/healt.../caffeine.html cites these caffeine concentrations: Tea (5 oz) Brewed for 3 minutes--------------------------- 20-46 Brewed for 1 minute -----------------------------9-33 That is to say, after steeping 1 minute at an unspecified temperature (but most people would assume near boiling) at least 11 to 13 mg of caffeine is yet to emerge from the leaves. A British government study http://archive.food.gov.uk/maff/arch...144/annexc.htm found that a 1-minute infusion from a teabag had 30% less caffeine than a 5-minute infusion. They're talking about finely chopped leaves here, and presumably very hot water, and still 30% remains after a minute. > That's an informed guess, because it's what I do. Too much caffeine just > keeps me awake at night; I only have a cup every month or two, Are you referring to coffee here? Or late-night tea? > and have a low tolerance. Theophylline OD makes me quite ill. So if > I'm having more than one mug of strong Assam or one pot of sencha, > I'll wash out most of the theophylline per above. Cold water seems > to work pretty well, though I have yet to try it on expensive > oolongs. I'm a little dubious about cold water, because I actually use tepid water a lot to brew tea in the summer. (I don't really like iced tea.) I find that a 15-minute steep of a green yields a delicious cup with no astringency at all, which gives a kind of creamy mouth feel. I've no idea how much caffeine there is in the cup, but clearly a lot of the good stuff in the leaves comes out in 15 minutes, so I'm not sure I'd want to toss the liquor from a 5-minute steep in tepid water. /Lew --- Lew Perin / http://www.panix.com/~perin/babelcarp.html |
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(Did we ever decide what what tea is, by the way?)
Peter "Lewis Perin" > wrote in message news ![]() > "Dog Ma 1" (reply w/o spam)> writes: > > > [...caffeine and steeping...] > > > > I'm going to hazard a guess that for most teas, a few minutes in tepid water > > will take out most of the alkaloids and not much else. That five seconds in > > hot water will take out 90% from anything. And that in fannings/dust and > > even small broken-leaf blacks, with most of the taste in dried surface > > exudates, only cold water will remove buzz w/o taking away too much flavor. > > I've just been trying to find some data on caffeine's extraction from > tea leaves as a function of steep temperature and time. (Using the > lazy man's research tool: Google.) Regarding temperature, there's > lots of talk about how lower steep temperatures slow down the > extraction, but not numbers. > > A Canadian university student health pamphlet > > http://www-health.concordia.ca/healt.../caffeine.html > > cites these caffeine concentrations: > > Tea (5 oz) > > Brewed for 3 minutes--------------------------- 20-46 > > Brewed for 1 minute -----------------------------9-33 > > That is to say, after steeping 1 minute at an unspecified temperature > (but most people would assume near boiling) at least 11 to 13 mg of > caffeine is yet to emerge from the leaves. > > A British government study > > http://archive.food.gov.uk/maff/arch...144/annexc.htm > > found that a 1-minute infusion from a teabag had 30% less caffeine > than a 5-minute infusion. They're talking about finely chopped leaves > here, and presumably very hot water, and still 30% remains after a > minute. > > > That's an informed guess, because it's what I do. Too much caffeine just > > keeps me awake at night; I only have a cup every month or two, > > Are you referring to coffee here? Or late-night tea? > > > and have a low tolerance. Theophylline OD makes me quite ill. So if > > I'm having more than one mug of strong Assam or one pot of sencha, > > I'll wash out most of the theophylline per above. Cold water seems > > to work pretty well, though I have yet to try it on expensive > > oolongs. > > I'm a little dubious about cold water, because I actually use tepid > water a lot to brew tea in the summer. (I don't really like iced > tea.) I find that a 15-minute steep of a green yields a delicious cup > with no astringency at all, which gives a kind of creamy mouth feel. > I've no idea how much caffeine there is in the cup, but clearly a lot > of the good stuff in the leaves comes out in 15 minutes, so I'm not > sure I'd want to toss the liquor from a 5-minute steep in tepid water. > > /Lew > --- > Lew Perin / > http://www.panix.com/~perin/babelcarp.html |
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Peter > wrote:
>(Did we ever decide what what tea is, by the way?) Properly, steeped leaves from the tips of the branches of the Camellia Sinensis bush. Informally, steeped herbs of any kind. --Blair "'Texas Tea', f'rinstance." |
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