tag:blogger.com,1999:blog-16115542.post8252202252453680122..comments2024-03-16T11:51:28.412-04:00Comments on CHA DAO: CAFFEINE AND TEA: Myth and Realitycoraxhttp://www.blogger.com/profile/03645573592247798140noreply@blogger.comBlogger63125tag:blogger.com,1999:blog-16115542.post-16592762580324915452022-03-10T05:38:56.170-05:002022-03-10T05:38:56.170-05:00Ron, Caffeine is very sparsely soluble in cold wat...Ron, Caffeine is very sparsely soluble in cold water (2.17 g/100 ml @ 25 deg ) whereas solubility is 20.0g/100ml @ 80 deg C and 66.6g/100m,l at 100 deg C I don't believe a 5 or 10 minute soak in cold water would markedly affect the caffeine content of the remaining leaves. Nigel Melicanhttps://www.blogger.com/profile/03411898106071232380noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-30462762001525531812022-03-09T14:48:06.718-05:002022-03-09T14:48:06.718-05:00Thanks for this complet and deep article. It is al...Thanks for this complet and deep article. It is always nice to find information based on experiments and not believes. Is difficult to find information on internet about this topic based in results. Thnaks for that!Delica Té Zenhttps://delica-te-zen.com/comprar-te-blanco/te-blanco-fresa-papayanoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-48317889312546964112020-03-14T23:16:41.103-04:002020-03-14T23:16:41.103-04:00Caffeine is very soluble. Using cold water to deca...Caffeine is very soluble. Using cold water to decaffeinate tea for five or ten minutes should be a matter of interest, as it may would not remove a lot of the flavoring from the tea. Anyway, this is what I do if I want tea before bedtime and it seems to work. I know this is anecdote and not science.Ronhttps://www.blogger.com/profile/00845676752635244417noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-11897320369338732342016-06-07T08:41:31.674-04:002016-06-07T08:41:31.674-04:00Has the author answered the above question (using ...Has the author answered the above question (using the data in reverse): If you brew tea for 1 minute only, would you achieve about 80% caffeine removal? Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-88558227777241785152016-02-12T23:45:13.701-05:002016-02-12T23:45:13.701-05:00Given that the articles referred to show a slower ...Given that the articles referred to show a slower extraction of caffeine, this also means that a high proportion of caffeine is left unextracted by the tea drinker. I aren't many tea lovers that steep tea more than 5 minutes. It would be interesting to measure caffeine extraction when loose leaves are steeped multiple times. When steeping tea for a long time, the water cools off, while with flash brewing each round comes with fresh hot water.Sam Linhttps://www.blogger.com/profile/14599630768687077478noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-51973180621982021562016-01-07T11:35:30.053-05:002016-01-07T11:35:30.053-05:00A magnetic stirrer is a standard piece of laborato...A magnetic stirrer is a standard piece of laboratory equipment that allows a glass vessel of liquid to be stirred by a small plastic coated magnetic rod in the liqid (termed a flea) which is magnetically attracted by a rotating magnet in the heating plate on which the glass vessel stands. I remember them being introduced in the 1960s - they saved a lot of time-consuming manual stirring with a glass or metallic stirrer. <br /> <br />Nigel at Teacraftnigelhttps://www.blogger.com/profile/11499563802830072418noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-64440122921126131012015-12-29T14:27:36.936-05:002015-12-29T14:27:36.936-05:00Surely you must mean "metallic" stirrer ...Surely you must mean "metallic" stirrer in the description of the first experiment, not "magnetic" stirrer. Although introducing a magnet into the mix might be interesting...Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-82132814869861056432015-12-08T10:07:07.531-05:002015-12-08T10:07:07.531-05:00Hi Anonymous(6.17PM). Since I wrote this caffeine ...Hi Anonymous(6.17PM). Since I wrote this caffeine blog in 2008 more studies have appeared - notably and most extensively "Caffeine in Chiang Rai tea infusions: effects of tea varaiety, type, leaf form, and infusion conditions" by Siripat Suteerapataranon et al. Food Chem. 114, 1335-1338, 2009. This clearly shows an inverse logarithmic relationship between 0 and 5 minutes where I had use a straight line interpolation. In the event it has very little effect on my conclusion that a 30 second steep cannot in any way be heralded as a panacea for home decaffeinators.<br /><br />Nigel at Teacraft Nigel Melicannoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-14910391438920120532015-12-08T10:06:28.280-05:002015-12-08T10:06:28.280-05:00Hi Anonymous(6.17PM). Since I wrote this caffeine ...Hi Anonymous(6.17PM). Since I wrote this caffeine blog in 2008 more studies have appeared - notably and most extensively "Caffeine in Chiang Rai tea infusions: effects of tea varaiety, type, leaf form, and infusion conditions" by Siripat Suteerapataranon et al. Food Chem. 114, 1335-1338, 2009. This clearly shows an inverse logarithmic relationship between 0 and 5 minutes where I had use a straight line interpolation. In the event it has very little effect on my conclusion that a 30 second steep cannot in any way be heralded as a panacea for home decaffeinators.<br /><br />Nigel at Teacraft nigelhttps://www.blogger.com/profile/11499563802830072418noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-41949990229510293742015-12-08T10:05:09.532-05:002015-12-08T10:05:09.532-05:00Hi Anonymous(6.17PM). Since I wrote this caffeine ...Hi Anonymous(6.17PM). Since I wrote this caffeine blog in 2008 more studies have appeared - notably and most extensively "Caffeine in Chiang Rai tea infusions: effects of tea varaiety, type, leaf form, and infusion conditions" by Siripat Suteerapataranon et al. Food Chem. 114, 1335-1338, 2009. This clearly shows an inverse logarithmic relationship between 0 and 5 minutes where I had use a straight line interpolation. In the event it has very little effect on my conclusion that a 30 second steep cannot in any way be heralded as a panacea for home decaffeinators.<br /><br />Nigel at Teacraft nigelhttps://www.blogger.com/profile/11499563802830072418noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-55321978984362896012015-12-08T03:45:15.274-05:002015-12-08T03:45:15.274-05:00Thank you Anonymous (6.17PM) for your valid point....Thank you Anonymous (6.17PM) for your valid point. <br /><br />Since I wrote this caffeine blog in 2007 some further studies have been made - notably and quite extensively in "Caffeine in Chiang Rai tea infusions: effects of tea variety, type, leaf form, and infusion conditions" by Siripat Suteerapataranon et al. Food Chem. 114, 1355-1338, 2009, which at least shows that the caffeine diffusion (which for I extrapolated between 0 and 5 minutes) follows an inverse logarithmic response, as might be expected, though over the timescale involved has very little real effect on my conclusion that a 30 second steep is not a panacea for home decaffeination.<br /><br />Nigel at Teacraftnigelhttps://www.blogger.com/profile/11499563802830072418noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-40563797588923910682015-12-07T18:17:57.640-05:002015-12-07T18:17:57.640-05:00Wait a minute. I just read the "Tea Preparati...Wait a minute. I just read the "Tea Preparation and its Influence on Methylxanthine" study and they only tested the amount of caffeine extracted at the 5, 10 and 15 minute marks. You can NOT simply extrapolate to determine the amounts extracted below the 5 minute mark. Without actually measuring the caffeine extracted at these time points you can not know whether the extraction is linear or logarithmic.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-41371813531883467672015-11-08T09:35:00.579-05:002015-11-08T09:35:00.579-05:00(November 2015)
I tried to find an answer to the o...(November 2015)<br />I tried to find an answer to the ole '30 second extraction' idea a year or two ago and found graphs that, all put together, gave me the impression that most of the caffeine would be in the liquid after 2 - 3 minutes of steeping the tea (loose leaf in a teapot, strained while pouring). <br />This is my personal experience; I 'feel' the caffeine from that first 2-minute brew from any color tea. If I 're-brew' the same leaves for 3 more minutes I don't 'feel' the caffeine. <br />But - the first brew of 2 minutes tastes great! Full flavor! Yum.<br />The second brew has no scent and tastes ... watery, with much less flavor. The only exception I have found is an Oolong tea which adds flavor to the second and possibly the third brews.<br />I noticed no one mentions how the tea tastes after a short brew compared to using the leaves again...<br />My solution (no pun intended ;-) is to brew the leaves twice, first for 2 minutes, I enjoy a cup of caffeine-charged tea while brewing the leaves a second time. I then mix all the tea for what I call a 'caffeine-reduced' beverage. That I store in the refrigerator and reheat for my morning cups as long as it lasts. That 'combined' tea never gives me the jitters that the first 2-minute brew does. <br />My conclusions - A high percentage of the caffeine must be in the liquid after a 2 minute brew. A lot less is in the second brew. The two mixed together gives me a nice balance that my body can handle, and the flavor is nice.<br />By the way, terrible as it sounds to the tea aficionados (sorry!), I simply use boiling water with all my tea. I don't have time or the technology to figure out the water temperature before pouring it into the pot. I suspect most casual tea drinkers do the same.<br />And, by what I have read, boiling water probably extracts the caffeine faster than a lower temperature.<br />I recommend for those folks who can't drink 'any' caffeine to drink herb teas, sorry.<br />Also, you non-caffeine drinkers, stay away from hot chocolate with real cacao. I learned that from experience. <br />:-)VTGinahttps://www.blogger.com/profile/17504835668401434932noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-3061648085391665742015-09-26T07:22:56.129-04:002015-09-26T07:22:56.129-04:00After reading the article & skimming through a...After reading the article & skimming through all comments as thoroughly as possible, I noticed that no experiments or evidence is given as to (approx.)HOW MUCH CAFFEINE would there be in the SECOND steeping of teabag in clear, hot water?? This WOULD change the parameters would it not? A % of caffeine is already left in first wash,THEN tea (bags/leaves) are resteeped in boiling water 2nd time. Possibly the pH of clear water is different than partially steeped tea & further steeping in new water would change rate or % of extraction. I'm just theorizing 2 clarify my point here, but to me, the whole question of hot water washes & caffeine levels has only been HALF addressed by the experiments & corresponding tables of data. Would be very interested in seeing future test results.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-76511580506999713792015-09-09T08:20:20.970-04:002015-09-09T08:20:20.970-04:00To complicate matters further, I'd like to poi...To complicate matters further, I'd like to point out to people that resteep their tea leaves that the caffeine extraction per time will be different than someone that's doing one long extraction for the same amount of time as their multiple extractions, because in between steeps the leaves stay wet and 1) compounds are extracting into the water clinging to the leaves between steeps and 2) the time the leaves are wet but not steeping is still softening the leaves and making it easier for compounds to come out once they're steeped again. I suspect that five one-minute extractions (with a few minutes between each extraction) will extract more caffeine in total that one continuous five minute extraction. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-58381257703117046792015-07-26T18:02:20.886-04:002015-07-26T18:02:20.886-04:00I know it's generally bad form to comment on a...I know it's generally bad form to comment on a blog post this old, but I found something in a publication in the Journal of Ethnopharmacology that may be relevant to this discussion. This study involved interviewing tea farmers in Yunnan on their perception of the health benefits of tea produced in different seasons and then comparing their responses to chemical analyses of the teas. According to the authors "No correlation was found between informants’ perceptions of stimulant properties and [caffeine content]." So even if you could know that black tea was higher in caffeine than green, that wouldn't necessarily mean that they'd be different enough for you to notice.<br /><br />Ahmed S, Unachukwu UJ, Stepp JR, et al (2010) Pu-erh tea tasting in Yunnan, China: Correlation of drinkers’ perceptions to phytochemistry. Journal of Ethnopharmacology 132:176–185. doi: 10.1016/j.jep.2010.08.016Aariqhttps://www.blogger.com/profile/17122876285963970642noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-63121811831162470842014-10-16T22:38:13.753-04:002014-10-16T22:38:13.753-04:00Just noticing what Anonymous said. According to Ni...Just noticing what Anonymous said. According to Nigels first table I would be better off to steep my tea for only one minute and drink tea that was only 18% of the usual caffine of that tea. Excellent observation! This is one reason I would like to know more. Maybe one day.<br /><br /> 30 seconds: 9% caffeine removal<br />1 minute: 18% caffeine removal<br />2 minutes: 34% caffeine removal<br />3 minutes: 48% caffeine removal<br />4 minutes: 60% caffeine removal<br />5 minutes: 69% caffeine removal<br />10 minutes: 92% caffeine removal<br />15 minutes: 100% caffeine removal<br />ponyjoehttps://www.blogger.com/profile/11547639970435218497noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-55879433345736375182014-10-16T22:14:36.147-04:002014-10-16T22:14:36.147-04:00I found on the internet a 2010research paper from ...I found on the internet a 2010research paper from Addis Ababa University in Ethiopa that seems to support the findings by the Spiro study. In one part of this study four Ethiopian teas Addis, black lion, cinnamon black and green tea were immersed into 30ml water at 94 degrees c and stirred for 3 minutes. The results were about 65% of the caffine was extracted. <br />Another finding was that higher temperatures increased the total amount of caffeine removed.<br /><br />I became interested in removing caffeine from tea when several years ago I was diagnosed with irritable bowel syndrome and told to avoid all caffine forever. After staying off all caffeine for months and trying decaf tea which I did not care for I became 100% better. I read on the internet the 30 minute decaf and tried it with the result of getting sick again. Not willing to give up so easily I went to a minute and a half. To my relief I did fine. I then went to a minute and was still not sufferring any ill. After some trial and error I have been steeping the tea for a little over a minute and doing fine. I find the tea has a lot more flavor than the 97% decaf variety. <br />In my case I did not need to go to fully decaf tea and maybe others are in the same boat i am. I would really like to see someone do a study at lower steeping times and using different methods of brewing the tea.<br />I found this article to be one of the best articles on the internet. Thanks much.ponyjoehttps://www.blogger.com/profile/11547639970435218497noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-31720316481043399262013-08-31T15:15:12.996-04:002013-08-31T15:15:12.996-04:00This is a most interesting article. Thank you Nige...This is a most interesting article. Thank you Nigel. However, I am still left wondering how much caffeine I am consuming per cup. Most frustrating that I could be drinking another cup per day without harming my unborn child! <br /><br />You mention two facts, which leave me wondering if they cancel each other out: <br /><br />1)Indian cafes tend to boil the tea to extract the most caffeine (this explains why they add so much sugar and milk!).<br /><br />2) Turkish teas tend to be lower in caffeine due to older bushes, more mature leaves, and their drying methods (if I've understood correctly?).<br /><br />Would I be right in assuming, then, that if I made a jug of Masala Chai, using the method below, there would be a lower level of caffeine in my cup than the average cup of PG tips?<br /><br />1) Boil the spices for 5 minutes<br />2) Add the tea leaves and boil for 45 seconds<br />3) Leave to steep for 1 minute then strain immediately<br />4) Store in fridge and reheat with milk and sugar to taste<br /><br />(8 tbsp of tea is used to 6 cup measures of water and my husband claims it tastes weak)<br /><br />Sorry if this is too specific for you. I wish there was a cheap way of measuring caffeine content too, otherwise we wouldn't all be in this pickle. <br /><br />EmilyAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-79293387631267642092013-06-15T19:39:38.922-04:002013-06-15T19:39:38.922-04:00Thanks Nigel,
So, would I be right to infer that ...Thanks Nigel, <br />So, would I be right to infer that instead of tipping out the first 30 seconds of steeped tea, just remove the bag and drink that first steep, then in would only be having about 20% of the caffeine?<br />KirstyAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-37661969358366215942013-06-14T05:35:34.938-04:002013-06-14T05:35:34.938-04:00Hi Nigel
what an interesting article and responses...Hi Nigel<br />what an interesting article and responses. I am in a very particular situation. I have found that I am very sensitive to caffeine and a cup of green tea at 4pm has me sleepless at 2 am. Not exaggerating. So years ago I stopped drinking tea and coffee. I now have a pretty severe return of childhood eczema and there appears to be some good evidence from japan that drinking Oolong can be very therapeutic. They tested 1 litre of oolong (35g tea) a day, divided into 3 after meal doses. I want to try it but before I start with just a teaspoonful I thought I would seek some more scholarly advice. I have read all the myths you discuss and now wonder what you would do if you wanted to drink oolong but wanted to minimise caffeine?penelopenoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-77718016579563354512013-01-28T20:26:22.850-05:002013-01-28T20:26:22.850-05:00Thank you so much! I will just keep the white tea ...Thank you so much! I will just keep the white tea for my husband (he drinks a lot of red bull to keep him going on a 12hrs. work day, I am hoping this will substitute it). If not then it would make a nice gift. I will definitely order rooibos herbal tea! Thank you so much Nigel! This particular blog is heaven sent and full of information. Keep it up and blessings! Jinnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-73505282263119390292013-01-28T03:25:11.303-05:002013-01-28T03:25:11.303-05:00Hi Anonymous, your tea vendor should know better -...Hi Anonymous, your tea vendor should know better - it is well established now that all teas derived from buds are very high in caffeine - white tea having some of the highest levels of all. If your vendor misinformed you I would advise returning the tea to him for a refund or exchange. As my blog clearly shows there is no quick home based method for decaffeination. Unfortunately all hot water methods will remove the other beneficial compounds (AOX polyphenols and theanine) in equal or larger ratio to the caffeine removed. If you wish to reduce your caffeine intake slightly you need to either make youy tea weaker (less leaf), or switch over to oolong teas (generally lower in caffeine than white teas. BUT if you need to cut out caffeine totally you should switch to caffeine free rooibos herbal tea (this has good AOX profile). Note that even "decaffeinated" teas still contain some caffeine. BTW, congratulations on your pregnancy.nigelhttps://www.blogger.com/profile/11499563802830072418noreply@blogger.comtag:blogger.com,1999:blog-16115542.post-63567633119413435112013-01-27T00:37:11.886-05:002013-01-27T00:37:11.886-05:00:-( I just ordered a bulk (5oz) of organic white t...:-( I just ordered a bulk (5oz) of organic white tea silver needle! I read that they contain the least caffeine and the most antioxidants! I'm pregnant so I watch my caffeine and now I am so upset knowing this. Nigel can you give me a way to decaffeinating the white tea in hot water wash? How long in minutes to steep it to remove 80% of the caffeine and in what temperature. Also, will hot water wash reduce the antioxidants in the white tea? I don't mind the inferior flavor after the wash as long as I know I keep my caffeine checked. Let me know :) thanks!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-16115542.post-68847957554783499102013-01-20T12:24:39.182-05:002013-01-20T12:24:39.182-05:00"The proof is in the pudding"...
Having ..."The proof is in the pudding"...<br />Having had crippling sleeping problems, due to a rare poisoning, I had to honestly examine the effects that my once-so-loved cup of tea might be contributing to that problem. So I just went off all caffeinated tea, with immediate (better sleeping) results. Then I heard about the "quick, 30-sec. decaff trick"and found,once again, I was suffering from those sleepless nights! Again, I went off all "quick decaff" tricks and, what do you know? I have some semblance of a "good night's sleep"once more! So,after having experimented, (knowing nothing about these afore-mentioned studies, with their scientific proofs), I have come to see the validity of there being influential vestiges of caffeine present, even with the "quick trick" (for someone who is hyper-sensitive to any stimulant; i.e., myself).<br />Hence, "the proof is in the pudding".<br />The solution is quite simply; abstinence! Like I read in one of the articles; caffeine was part of what God intended tea to have, so I must bow my head to this fact! I can't try to change its composition, and still effect a better night's sleep; "have my cake and eat it, too", but I can eliminate it altogether and KNOW I will be sleeping better! So, there you have it... <br />The afore-mentioned research has helped to confirm what I had not wanted to face: give it up! Thank you, sirs, for that confirmation! And, "good night"!Anonymousnoreply@blogger.com