water temperature and green tea

Hi all, I don't want to open yet another debate on tea. Please, if you feel the need to flame, select another topic. I just need answers to a couple of questions.
As a long time black tea / tisane drinker, tea to me meant boiling some water, pouring it over tea leaves / herbs and decanting after some time. Only within the last 5 years have I been introduced to other kinds of tea and other methods of preparation. And even though I've done it for some time now, I don't feel that I've mastered those techniques either. I still use a thermometer and I often start over. I have several questions about this:
1. What happens to tea if the water isn't hot enough? I understand that if the water is too hot, it 'burns off' some of the compounds so they evaporate quickly and the taste changes. So, by this logic, wouldn't a longer brew time in cooler water result in similar brew? I tried this with some greens that I have, and it was about the same. I've really not got any expensive greens yet (waiting for my order) so I can't tell whether it's like that with them too. What is your view? 2. Several of the greens that I've tried have a sort of a spinach taste to them. Is this a desirable taste in greens? If not, what am I doing wrong to produce this kind of a taste? 3. Do you prefer to heat the water to the desired temperature or to boil it and let it cool to that temperature? If you have a preference, why? 4. Do you like your tea strong or weak? I seem to prefer weak, I usually disagree with amounts of tea recommended. This has also changed once I started to get some better quality leaves - they don't brew the same way that grocery store loose leaf tea brews. With those I used to brew only about 1/4 of recommended amount but with whole leaves I tend to brew about 1/2 amt recommended. I've also heard of people using a scale to weight the leaves so they get an exact amount. Where does one find such a scale? (It'd have to be able to weigh grams accurately, right?)
Thanks for all your help,
~sara
Reply to
Sara Hawk
> > 1. What happens to tea if the water isn't hot enough? I understand that if > the water is too hot, it 'burns off' some of the compounds so they evaporate > quickly and the taste changes. So, by this logic, wouldn't a longer brew > time in cooler water result in similar brew? I tried this with some greens > that I have, and it was about the same. I've really not got any expensive > greens yet (waiting for my order) so I can't tell whether it's like that > with them too. What is your view? what types of green tea have you tried? > 2. Several of the greens that I've tried have a sort of a spinach taste to > them. Is this a desirable taste in greens? If not, what am I doing wrong > to produce this kind of a taste? some of teas do have a distinctive spinach taste- i do not like these- > 3. Do you prefer to heat the water to the desired temperature or to boil it > and let it cool to that temperature? If you have a preference, why? i heat water to desired temperature- using either a thermometer or my eyes(looking at bubbles) > 4. Do you like your tea strong or weak? I seem to prefer weak- i do - i usually use the suggested amount-wooden tea spoon
joanne
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Reply to
Joanne Rosen
> Hi all, > I don't want to open yet another debate on tea. Please, if you feel the > need to flame, select another topic. I just need answers to a couple of > questions. > As a long time black tea / tisane drinker, tea to me meant boiling some > water, pouring it over tea leaves / herbs and decanting after some time. > Only within the last 5 years have I been introduced to other kinds of tea > and other methods of preparation. And even though I've done it for some > time now, I don't feel that I've mastered those techniques either. I still > use a thermometer and I often start over. I have several questions about > this: > > 1. What happens to tea if the water isn't hot enough? Then the tea leafs won't release the full fragrance and taste. Your folded tea leafs needs to be unfolded with proper water temperature. I understand that if > the water is too hot, it 'burns off' some of the compounds so they evaporate > quickly and the taste changes. Very true. So, by this logic, wouldn't a longer brew > time in cooler water result in similar brew? I tried this with some greens > that I have, and it was about the same. I've really not got any expensive > greens yet (waiting for my order) so I can't tell whether it's like that > with them too. What is your view? when you boil your water- some minerals start loosing it's contains. This contains has a reaction with tea. So over boiling water loose too much minerals with might makes the taste of your tea- dull, flat, biter etc. > 2. Several of the greens that I've tried have a sort of a spinach taste to > them. Is this a desirable taste in greens? If not, what am I doing wrong > to produce this kind of a taste? Most probably you are over steeping your tea,can be for the qualities of the green tea and also the water. Quality of water is very important too. > 3. Do you prefer to heat the water to the desired temperature or to boil it > and let it cool to that temperature? If you have a preference, why? for my green tea only:- when the water is near to roiling boil, i stop hiting the water then wait 30 seconds(Cool down the water a little) and start steeping my green tea. Also depend which brewing method I am using- Gaiwan or kettle. My advice is for green tea-Kung Fu Cha brewing method is not good. > 4. Do you like your tea strong or weak? I seem to prefer weak, I usually > disagree with amounts of tea recommended. This has also changed once I > started to get some better quality leaves - they don't brew the same way > that grocery store loose leaf tea brews. With those I used to brew only > about 1/4 of recommended amount but with whole leaves I tend to brew about > 1/2 amt recommended. I've also heard of people using a scale to weight the > leaves so they get an exact amount. Where does one find such a scale? > (It'd have to be able to weigh grams accurately, right?) Well, its depend what types of tea I am drinking. For black I always prefer strong. Green and oolong light. I also disagree with tea amount recommendation but I try to follow some standard basic. Quality of tea is important, always. I think when someone always makes tea-scale is not so important as long as i have a tea spoon with me. Well you can also use a regular scale for spices. Again about steeping your tea- just follow your heart. I strongly believe little bit of extra or less loose tea doesn't change the taste much. Also little high or low water temperature and one minute (+,-) doesn't matter. You know your taste better then anyone else. Enjoy your cup of tea. Ripon (From Bangladesh) > ~sara
Reply to
Ripon
"Sara Hawk" wrote in news:Lfswb.295275$Fm2.311652@attbi_s04: > Hi all, > I don't want to open yet another debate on tea. Please, if you feel > the need to flame, select another topic. I just need answers to a > couple of questions. The questions you ask are important, and have indeed been discussed here before with a great deal of vigor. :-) > > As a long time black tea / tisane drinker, tea to me meant boiling > some water, pouring it over tea leaves / herbs and decanting after > some time. Only within the last 5 years have I been introduced to > other kinds of tea and other methods of preparation. And even though > I've done it for some time now, I don't feel that I've mastered those > techniques either. I still use a thermometer and I often start over. > I have several questions about this: > > 1. What happens to tea if the water isn't hot enough? I understand > that if the water is too hot, it 'burns off' some of the compounds so > they evaporate quickly and the taste changes. So, by this logic, > wouldn't a longer brew time in cooler water result in similar brew? I > tried this with some greens that I have, and it was about the same. > I've really not got any expensive greens yet (waiting for my order) so > I can't tell whether it's like that with them too. What is your view? The flavors in tea come from various compounds in it. Some compounds dissolve at lower temperatures, some need higher temperatures. Some dissolve quickly, others slowly. So, a long steep at a low temperature is not necessarily the same as a short steep at a higher temperature. See below. > 2. Several of the greens that I've tried have a sort of a spinach > taste to them. Is this a desirable taste in greens? If not, what am > I doing wrong to produce this kind of a taste? There are strong opinions on this. I belong to the faction that believes that the "spinach" taste (sometimes called "grassy") comes from steeping at too high a temperature. Try steeping the same tea at a lower temperature and see if the taste is different. > 3. Do you prefer to heat the water to the desired temperature or to > boil it and let it cool to that temperature? If you have a preference, > why? I heat and then cool (a method I have seen on some Japanese tea websites). One might argue that there will be more dissolved air (a good thing) in water that is heated to the target temperature and no more, but if there is a difference it might not be noticable to (any? some? most?) palates. >4. Do you like your tea strong or weak? I seem to prefer weak, I > usually disagree with amounts of tea recommended. This has also > changed once I started to get some better quality leaves - they don't > brew the same way that grocery store loose leaf tea brews. With those > I used to brew only about 1/4 of recommended amount but with whole > leaves I tend to brew about 1/2 amt recommended. I've also heard of > people using a scale to weight the leaves so they get an exact amount. > Where does one find such a scale? (It'd have to be able to weigh > grams accurately, right?) Strength of tea is a matter of personal taste. The tea in tea bags is like dust. Very fine tea like that is called fannings. It gives up its flavor very quickly. As you observe, if you brew similar weights of fannings and whole-leaf tea for the same amount of time in the same amount of water, the tea made with fannings will be much stronger, because more surface area is exposed to the hot water. Rather than using more or less tea, you might want to try varying the amount of time that you brew the tea. Overbrewing tea can make it bitter. You may find that you prefer a larger amount of tea brewed a shorter period of time compared with a lesser amount of the same tea brewed for a longer period. There has been much controversy about scales. There are two questions, really. One is how accurate you have to be. The other is whether it is easy to judge the right amount of tea using a spoon. As for the first question, while some people may claim to be able to tell the difference that a 1/10 of a gram of tea can make, that amount of accuracy may be (probably is) overkill. Typically, brewing recommendations by weight are about 2.25 or 2.5 grams per 6 ounces of water. (Talk about mixed measurements!) If you are measuring normal whole-leaf tea that is not particularly fluffy, the weight of a teaspoon's worth of tea is in or close to that range. OTOH, CTC tea and other teas that are broken leaves (or smaller) weight more per teaspoon. For me, scales are most useful for fluffy teas. I'm completely at a loss when judging the right amount of fluffy tea by eye. Using a scale I know I am in the zone and I can get repeatable results, even if the tea has been fluffed up even more or compacted. The scale that I use (a Tanita 1479 if memory serves) was purchased online. It is small, easy to use, and reasonably priced. > > Thanks for all your help, > > ~sara > > >
Good luck, and happy tea explorations!
Debbie
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Reply to
Debbie Deutsch
> Hi all, > I don't want to open yet another debate on tea. Please, if you feel the > need to flame, select another topic. I just need answers to a couple of > questions. > > As a long time black tea / tisane drinker, tea to me meant boiling some > water, pouring it over tea leaves / herbs and decanting after some time. > Only within the last 5 years have I been introduced to other kinds of > tea and other methods of preparation. And even though I've done it for > some time now, I don't feel that I've mastered those techniques either. > I still use a thermometer and I often start over. I have several > questions about this: > > 1. What happens to tea if the water isn't hot enough? I understand that > if the water is too hot, it 'burns off' some of the compounds so they > evaporate quickly and the taste changes. So, by this logic, wouldn't a > longer brew time in cooler water result in similar brew? I tried this > with some greens that I have, and it was about the same. I've really > not got any expensive greens yet (waiting for my order) so I can't tell > whether it's like that with them too. What is your view? > > 2. Several of the greens that I've tried have a sort of a spinach taste to > them. Is this a desirable taste in greens? If not, what am I doing wrong to > produce this kind of a taste? > > 3. Do you prefer to heat the water to the desired temperature or to boil it > and let it cool to that temperature? If you have a preference, why? I've experimented with both methods and have found that I prefer to heat to the desired temperature and then steep. To my palate, the taste is slightly better than with the other method. I watch the bubbles to guage temperature and don't use a thermometer. > 4. Do you like your tea strong or weak? I seem to prefer weak, I usually > disagree with amounts of tea recommended. This has also changed once I > started to get some better quality leaves - they don't brew the same way > that grocery store loose leaf tea brews. With those I used to brew only > about 1/4 of recommended amount but with whole leaves I tend to brew about > 1/2 amt recommended. I've also heard of people using a scale to weight the > leaves so they get an exact amount. Where does one find such a scale? > (It'd have to be able to weigh grams accurately, right?) Strength is a purely subjective matter. What one person finds strong, another may find weak etc. etc. On the matter of scales, I'd never tell anyone not to use one but for me, the variation between one brew of a particular tea and another can be interesting. 'Mistakes' can be a source of knowledge. > Thanks for all your help, > > ~sara
J
Reply to
John
Sara HawkLfswb.295275$Fm2.311652@attbi_s0411/24/03 13:39quietly_sereneSPAMMENOT@yahoo.com Sara, snip > 1. What happens to tea if the water isn't hot enough? I understand that if > the water is too hot, it 'burns off' some of the compounds so they evaporate > quickly and the taste changes. So, by this logic, wouldn't a longer brew > time in cooler water result in similar brew? I tried this with some greens > that I have, and it was about the same. I've really not got any expensive > greens yet (waiting for my order) so I can't tell whether it's like that > with them too. What is your view? It's been my experience that erring on the side of caution -- too cool rather than too hot -- yields a more pleasant cup of green tea. Generally, I've found that extremely fresh and young buds/leaves require a cooler temperature. Less fresh or larger leaves, higher. For greens, for me, lower means 135-145. Higher means 160-175; occasionally higher. And points in between. It calls for experimentation, which is what you'll want to do. > 2. Several of the greens that I've tried have a sort of a spinach taste to > them. Is this a desirable taste in greens? If not, what am I doing wrong > to produce this kind of a taste? You're doing nothing wrong, I'll bet. Some greens just taste that way. If they *all* taste like spinach, I dunno. Long jing and Lin yun decided taste most unspinach-like. Among others. > 3. Do you prefer to heat the water to the desired temperature or to boil it > and let it cool to that temperature? If you have a preference, why? I bring the water up to just over the desired temperature and then pour. I do not bring the water to a boil and let it cool. Why? Habit, and the mythological oxygen depletion theory, I guess. > 4. Do you like your tea strong or weak? I can live with "too weak" quite nicely. I don't like the taste when green tea becomes "too strong." >I seem to prefer weak, I usually > disagree with amounts of tea recommended. This has also changed once I > started to get some better quality leaves - they don't brew the same way > that grocery store loose leaf tea brews. With those I used to brew only > about 1/4 of recommended amount but with whole leaves I tend to brew about > 1/2 amt recommended. I've also heard of people using a scale to weight the > leaves so they get an exact amount. Where does one find such a scale? > (It'd have to be able to weigh grams accurately, right?) Quite right. I use a three beam gram scale accurate to the tenth of a gram. I also use a gram balance scale. Generally, I use half the number of grams of dry tea as ounces of water: 5 grams tea to 10 ounces water, for example. This usually works, and I adjust steep times around it. Remember you can expect multiple steeps from the same leaves. Therefore, use enough leaf, and cut the steep time down. Stinting on leaf amount compromises quality, I've found. David Hoffman of Silk Road Tea charges somewhere around $50 USC for a Chinese balance scale that works just fine. > I happily and unabashedly use a thermometer to guide me whenever I feel like I want its guidance, which is usually when I'm brewing a delicate green.
Best, Michael
Reply to
Michael Plant
> I bring the water up to just over the desired temperature and then > pour. I do not bring the water to a boil and let it cool. Why? Habit, > and the mythological oxygen depletion theory, I guess.
I'm sure this has been covered before, but what do you use to heat the water? I just have an old kettle on an electric stove so I can't know it's doing anything but boiling then have to wait for the temp to come back down. Please tell me a better way.
Reply to
Babba Rom Dos
Babba Rom Dos writes: > > I bring the water up to just over the desired temperature and then > > pour. I do not bring the water to a boil and let it cool. Why? Habit, > > and the mythological oxygen depletion theory, I guess. > > I'm sure this has been covered before, but what do you use to heat the > water? I just have an old kettle on an electric stove so I can't know it's > doing anything but boiling then have to wait for the temp to come back > down. Please tell me a better way.
You could use the same old kettle and bring down the water temperature by adding room-temperature water. Or you could pour the hot water back and forth between two vessels until it cools to the temperature you want.
/Lew --- Lew Perin / perin@acm.org
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Reply to
Lewis Perin
Lewis Perin wrote in news:pc7ad6kcvbt.fsf@panix1.panix.com: > Babba Rom Dos writes: > >> > I bring the water up to just over the desired temperature and then >> > pour. I do not bring the water to a boil and let it cool. Why? >> > Habit, and the mythological oxygen depletion theory, I guess. >> >> I'm sure this has been covered before, but what do you use to heat >> the water? I just have an old kettle on an electric stove so I can't >> know it's doing anything but boiling then have to wait for the temp >> to come back down. Please tell me a better way. > > You could use the same old kettle and bring down the water temperature > by adding room-temperature water. Or you could pour the hot water > back and forth between two vessels until it cools to the temperature > you want.
Yes, but that doesn't address the "mythological oxygen depletion theory"; the object here seems to be avoidance of exceeding the target temperature by more than a few degrees.
I have no opinion on this. I'm still figuring out how to make a decent cup of green tea, period.
-- fD
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fD
Reply to
fLameDogg
Babba Rom DosXns943E5A9BFA4A9jc1Gao9@65.83.225.25411/25/03 08:49julioYODUDEcastaneda@yahoo.com >> I bring the water up to just over the desired temperature and then >> pour. I do not bring the water to a boil and let it cool. Why? Habit, >> and the mythological oxygen depletion theory, I guess. > > I'm sure this has been covered before, but what do you use to heat the > water? I just have an old kettle on an electric stove so I can't know it's > doing anything but boiling then have to wait for the temp to come back > down. Please tell me a better way.
I stick a metal stick-thermometer into the kettle spout. Conversely -- and more and more lately -- I listen for the changing tone of the heating water. If you always use the same kettle, and always fill it to the same point, and always use the same amount of heat, you will actually hear changing tones. Or maybe this is just idiosyncratic to my kettle. But, anyway, that's my answer. (The thermometer has a wheel face at the top.)
BTW, regarding us having covered the topic before worry not: Redundant is our middle name.
Michael
Reply to
Michael Plant
The folks at Tea-n-Crumpets suggested an easy way to get water temperature for steeping green tea just right: use one part water at room temperature and three parts boiling water.
This works for me and makes a good cup of green tea.
Reply to
Robert Dunbar
One thing I do is pour boiling water from kettle into a pyrex cup. This cools it almost immediately to 180F. Then when poured into the teapot it's about 170F, which is fine for many green teas. This is for 10 oz. of water in a 10 oz. pot. Your own teaware may vary!
Of course, some greens perform better when cooler and some hotter. I get out the thermometer when it seems necessary, or when I'm experimenting with a new tea.
There are many ways to control temp, as you've read in previous posts.
Cheers, Joe.
Reply to
Joseph Kubera
I may regret this, but flame-proof suit is well-zipped...
On the temperature front, I'd say that whatever works for you is right. It IS true that for the great majority of serious sippers, black teas taste best if brewed at the highest possible temperature. That usually means fully boiling water and a hot pot, even at sea level - never had really good black tea at altitude, where boiling temp is reduced. I've even done the experiment of maintaining a boil in the microwave, and gotten better tea. Issue here is not to distill away delicate aromatics. (As a side-point, little aroma will be lost in normal brewing no matter how hot the water - has to do with partial vapor pressures of soluble volatiles in a very dilute solution.)
Green teas tend to get very bitter if overwarmed. Much of the unpleasant bitter stuff is rapidly soluble; hence the pre-rinse favored in some techniques. Note that brewing time and temperature are not interchangeable: a fast brew at boiling does not produce the same result as a longer steep at 80C. In Asia, unlike the US, many people seem to make a practice of multiple extractions from the same green leaves. Even with a fast pre-rinse in hot water, I find the second and third steeps to make a much nicer tea than the first; the fourth is pleasant but weak.
Tea brewing chemistry is not extremely complicated, but there's a lot of mythology. The "oxygen" thing is simply not true - not much there under any circumstances, and nil effect in the brew. What is true is that lime-rich water (which, IMO, makes the best tea) loses CO2 on boiling. This reduces the solubility of divalent (calcium and magnesium) salts, so they crust up in the kettle and leave less alkaline water - which then does a worse job of extracting slightly acidic polyphenols and other good things. (Alkaloids like theophylline are so soluble that none of this much matters, only full hydration of the leaf.) So a fresh boil of freshly drawn water is important IF you're fortunate to have slightly hard water. Where it's very pure, as in much of the northern UK, it makes little or no difference.
There's also some interesting stuff that happens later. For example, some of the tannins bind (not actually reacting) with the alkaloids, settling out in a fine floc and shifting flavor. This is one key reason why length of both steeping and standing matter: alkaloids are extracted very rapidly, tannins more gradually; and that flocculation takes a while too. The protein in even a minute amount of milk - not nearly enough to taste milky - has a similar effect.
One could go on. There's some very good research on tea available on the web, differing markedly from common mythology. I have a Ph.D. in organic chemistry, have read a number of scholarly treatises on tea technology and even worked a bit in the field - and I'd still say: forget all the stories, start with what old-timers recommend, vary everything and make careful observations. Then do the easiest (or most fun) thing that works for you.
-DM
Reply to
Dog Ma 1
Dog Ma 1tvJxb.349078$0v4.18989941@bgtnsc04-news.ops.worldnet.att.net11/28/03 10:06spamdogma_I@att.net reply w/o spam > I may regret this, but flame-proof suit is well-zipped... > > On the temperature front, I'd say that whatever works for you is right. It > IS true that for the great majority of serious sippers, black teas taste > best if brewed at the highest possible temperature. That usually means fully > boiling water and a hot pot, even at sea level - never had really good black > tea at altitude, where boiling temp is reduced. I've even done the > experiment of maintaining a boil in the microwave, and gotten better tea. > Issue here is not to distill away delicate aromatics. (As a side-point, > little aroma will be lost in normal brewing no matter how hot the water - > has to do with partial vapor pressures of soluble volatiles in a very dilute > solution.) > > Green teas tend to get very bitter if overwarmed. Much of the unpleasant > bitter stuff is rapidly soluble; hence the pre-rinse favored in some > techniques. Note that brewing time and temperature are not interchangeable: > a fast brew at boiling does not produce the same result as a longer steep at > 80C. In Asia, unlike the US, many people seem to make a practice of multiple > extractions from the same green leaves. Even with a fast pre-rinse in hot > water, I find the second and third steeps to make a much nicer tea than the > first; the fourth is pleasant but weak. > > Tea brewing chemistry is not extremely complicated, but there's a lot of > mythology. The "oxygen" thing is simply not true - not much there under any > circumstances, and nil effect in the brew. What is true is that lime-rich > water (which, IMO, makes the best tea) loses CO2 on boiling. This reduces > the solubility of divalent (calcium and magnesium) salts, so they crust up > in the kettle and leave less alkaline water - which then does a worse job of > extracting slightly acidic polyphenols and other good things. (Alkaloids > like theophylline are so soluble that none of this much matters, only full > hydration of the leaf.) So a fresh boil of freshly drawn water is important > IF you're fortunate to have slightly hard water. Where it's very pure, as in > much of the northern UK, it makes little or no difference. > > There's also some interesting stuff that happens later. For example, some of > the tannins bind (not actually reacting) with the alkaloids, settling out in > a fine floc and shifting flavor. This is one key reason why length of both > steeping and standing matter: alkaloids are extracted very rapidly, tannins > more gradually; and that flocculation takes a while too. The protein in even > a minute amount of milk - not nearly enough to taste milky - has a similar > effect. > > One could go on. There's some very good research on tea available on the > web, differing markedly from common mythology. I have a Ph.D. in organic > chemistry, have read a number of scholarly treatises on tea technology and > even worked a bit in the field - and I'd still say: forget all the stories, > start with what old-timers recommend, vary everything and make careful > observations. Then do the easiest (or most fun) thing that works for you. > > -DM > >
No need for the flame-proof suit, Dog. Your post is interesting, and your points are well taken, especially those in your last paragraph. Ultimately, tea must be more art than science.
Michael
Reply to
Michael Plant
> The folks at Tea-n-Crumpets suggested an easy way to get water temperature > for steeping green tea just right: use one part water at room temperature > and three parts boiling water. > This works for me and makes a good cup of green tea.
Okay, call in the mathematicians. First, assuming that you let the water run a bit to get some water fresh from the pipe (or that you just did let it run to fill up the kettle which is now boiling), the water might be a bit cooler than room temperature. At least in Wisconsin, unless the room is a cistern.
If tap water is 50 degrees, which is realistic where I sit watching the snow out of my window, then 3:1 gives you about 170 degree water. 4:1 gives you 180. Does the difference matter?
Attempting to avoid work (by looking out the window at snow and/or posting),
Rick.
Reply to
Rick Chappell
> I may regret this, but flame-proof suit is well-zipped... > > On the temperature front, I'd say that whatever works for you is right. It > IS true that for the great majority of serious sippers, black teas taste > best if brewed at the highest possible temperature. That usually means fully > boiling water and a hot pot, even at sea level - never had really good black > tea at altitude, where boiling temp is reduced. I've even done the > experiment of maintaining a boil in the microwave, and gotten better tea. > Issue here is not to distill away delicate aromatics. (As a side-point, > little aroma will be lost in normal brewing no matter how hot the water - > has to do with partial vapor pressures of soluble volatiles in a very dilute > solution.) > > Green teas tend to get very bitter if overwarmed. Much of the unpleasant > bitter stuff is rapidly soluble; hence the pre-rinse favored in some > techniques. Note that brewing time and temperature are not interchangeable: > a fast brew at boiling does not produce the same result as a longer steep at > 80C. In Asia, unlike the US, many people seem to make a practice of multiple > extractions from the same green leaves. Even with a fast pre-rinse in hot > water, I find the second and third steeps to make a much nicer tea than the > first; the fourth is pleasant but weak. > > Tea brewing chemistry is not extremely complicated, but there's a lot of > mythology. The "oxygen" thing is simply not true - not much there under any > circumstances, and nil effect in the brew. What is true is that lime-rich > water (which, IMO, makes the best tea) loses CO2 on boiling. This reduces > the solubility of divalent (calcium and magnesium) salts, so they crust up > in the kettle and leave less alkaline water - which then does a worse job of > extracting slightly acidic polyphenols and other good things. (Alkaloids > like theophylline are so soluble that none of this much matters, only full > hydration of the leaf.) So a fresh boil of freshly drawn water is important > IF you're fortunate to have slightly hard water. Where it's very pure, as in > much of the northern UK, it makes little or no difference. > > There's also some interesting stuff that happens later. For example, some of > the tannins bind (not actually reacting) with the alkaloids, settling out in > a fine floc and shifting flavor. This is one key reason why length of both > steeping and standing matter: alkaloids are extracted very rapidly, tannins > more gradually; and that flocculation takes a while too. The protein in even > a minute amount of milk - not nearly enough to taste milky - has a similar > effect. > > One could go on. There's some very good research on tea available on the > web, differing markedly from common mythology. I have a Ph.D. in organic > chemistry, have read a number of scholarly treatises on tea technology and > even worked a bit in the field - and I'd still say: forget all the stories, > start with what old-timers recommend, vary everything and make careful > observations. Then do the easiest (or most fun) thing that works for you. > > -DM
Good article, one of the rare ones I save. I made the same observations living in pure-water Manchester and in lime-water Henley. Now I am in pure-water Cologne and I have to find other teas that suit the water. Oolong is great, black ones have to be carefully chosen. Green one is simply controlled by temperature.
JB
Reply to
J Boehm

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