The Science Behind Tetsubin

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CWarren
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Thu Jan 04, 2018 12:20 am

Seriously though have you not read my above scientific post? Iron kettle + Water + Heat + Tea = Tasty. Why are you still searching for answers after such overwhelming scientific truth? All these ions, kamayaki, compounds, f1,2,3, etc just complicates my simple formula. :D
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tealifehk
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Thu Jan 04, 2018 1:04 am

Trying to ensure they make your tea more tasty and not less tasty. :D
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tealifehk
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Thu Jan 04, 2018 1:09 am

https://japan-design.imazy.net/jp/craft ... on-kettle/

Translated from Japanese:

And it seems that only "bivalent iron ion (Fe 2 +)" can be absorbed in the human intestine. Therefore, "iron ion · iron" generated by touching the southern steel bottle with water is said to be easy for absorption and good for the body.
Even if it is said that it is generated from an iron bottle, it does not mean that it melts out greatly, and it can be taken from 1 to 2 mg with a single kettle. Since the required intake of iron is 12 mg per day, it is possible to take 1 to 20% of the necessary intake amount.
The refilling of iron by using the southern steel bottle is published in the research report of Mr. Keiko Oikawa, a medical doctor in charge of education at Iwate University.
(Reference paper 1 Keiko Oikawa, Anemia Improvement Effect of Iron Pot Eluate in Iron Deficiency Anemic Rat, Journal of Japanese Home Economics 47 (11), 1073-1078, 1996)
(Reference Article 2: Akiko Imano, Keiko Oikawa, cooking Changes in the amount of iron eluted from an iron pot, Journal of Japanese Culinary Science Journal 36 (1), 39-44, 2003)

So it seems the amount of iron eluted is pretty minor; would 1-2mg of iron in a whole pot of water even have a detectable effect on tea liquor? That's harder to answer. The iron should be usable by the body since it is reduced, but some won't be the moment the kettle starts to rust. It's interesting that even the 1-2mg can contribute a significant amount of iron to the body's daily needs, and it appears Fe 2+ is readily usable by the body. But how much of that is usable when it reacts with compounds in tea? And will this have a positive or negative effect?
Last edited by tealifehk on Thu Jan 04, 2018 1:29 am, edited 2 times in total.
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CWarren
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Thu Jan 04, 2018 1:16 am

tealifehk wrote:
Thu Jan 04, 2018 1:09 am
https://japan-design.imazy.net/jp/craft ... on-kettle/

Translated from Japanese:

And it seems that only "bivalent iron ion (Fe 2 +)" can be absorbed in the human intestine. Therefore, "iron ion · iron" generated by touching the southern steel bottle with water is said to be easy for absorption and good for the body.
Even if it is said that it is generated from an iron bottle, it does not mean that it melts out greatly, and it can be taken from 1 to 2 mg with a single kettle. Since the required intake of iron is 12 mg per day, it is possible to take 1 to 20% of the necessary intake amount.
The refilling of iron by using the southern steel bottle is published in the research report of Mr. Keiko Oikawa, a medical doctor in charge of education at Iwate University.
(Reference paper 1 Keiko Oikawa, Anemia Improvement Effect of Iron Pot Eluate in Iron Deficiency Anemic Rat, Journal of Japanese Home Economics 47 (11), 1073-1078, 1996)
(Reference Article 2: Akiko Imano, Keiko Oikawa, cooking Changes in the amount of iron eluted from an iron pot, Journal of Japanese Culinary Science Journal 36 (1), 39-44, 2003)
Tasty and healthy? I’m liking your findings so far. I’ll await with anticipation your continued research while I drink my tasty and healthy iron infused tea. :)
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tealifehk
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Thu Jan 04, 2018 1:18 am

The little bit of iron added will prevent iron deficiencies/anemia, which tea contributes to since polyphenols bind with iron in the body. It appears that tetsubin will slightly reduce astringency and bitterness, but also affect certain compounds in green tea that have health benefits. If you are drinking green tea for health purposes, tetsubin may not be what you want. On the other hand, if you get plenty of iron in your diet and aren't really concerned with the health benefits of green tea, go ahead and tetsubin it up! Tetsubin sound like the ticket for astringent/bitter pu erh that is over a year old.
Last edited by tealifehk on Thu Jan 04, 2018 1:46 am, edited 3 times in total.
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tealifehk
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Thu Jan 04, 2018 1:41 am

There's nothing on whether different heat sources make a difference, though, so maybe your one-hour wait for water to boil isn't really doing anything :lol:
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CWarren
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Thu Jan 04, 2018 1:45 am

tealifehk wrote:
Thu Jan 04, 2018 1:18 am
The little bit of iron added will prevent iron deficiencies/anemia, which tea contributes to since polyphenols bind with iron in the body. It appears that tetsubin will slightly reduce astringency and bitterness, but also affect certain compounds in green tea that have health benefits. If you are anemic or are drinking green tea for health purposes, tetsubin may not be what you want. On the other hand, if you get plenty of iron in your diet and aren't really concerned with the health benefits of green tea, go ahead and tetsubin it up! Tetsubin sound like the ticket for astringent/bitter pu erh that is over a year old.
I can’t cite sources but I’ve read many a statement over the years regarding tetsubins being better for puerh over green tea which was better suited for clay and stainless, etc kettles. Since the majority of my sessions are puerh related my tetsubin is doing me good. Thanks for more confirmation. I’ve made many a joke during this discussion but seriously enjoying the info even if I’m not a big tea science guy but then again I’m not a big tea spiritual guy either. I just enjoy tea, it’s look, aroma, taste and happy feels. Beyond that I find the information interesting but I don’t dwell on it.
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tealifehk
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Thu Jan 04, 2018 1:48 am

CWarren wrote:
Thu Jan 04, 2018 1:45 am
tealifehk wrote:
Thu Jan 04, 2018 1:18 am
The little bit of iron added will prevent iron deficiencies/anemia, which tea contributes to since polyphenols bind with iron in the body. It appears that tetsubin will slightly reduce astringency and bitterness, but also affect certain compounds in green tea that have health benefits. If you are anemic or are drinking green tea for health purposes, tetsubin may not be what you want. On the other hand, if you get plenty of iron in your diet and aren't really concerned with the health benefits of green tea, go ahead and tetsubin it up! Tetsubin sound like the ticket for astringent/bitter pu erh that is over a year old.
I can’t cite sources but I’ve read many a statement over the years regarding tetsubins being better for puerh over green tea which was better suited for clay and stainless, etc kettles. Since the majority of my sessions are puerh related my tetsubin is doing me good. Thanks for more confirmation. I’ve made many a joke during this discussion but seriously enjoying the info even if I’m not a big tea science guy but then again I’m not a big tea spiritual guy either. I just enjoy tea, it’s look, aroma, taste and happy feels. Beyond that I find the information interesting but I don’t dwell on it.
I'm just trying to make the best possible cup of tea, and getting into the science behind it helps me identify what is and isn't true, and why or why not! Nobody's done any research on whether different heat sources make any difference to cooking, let alone boiling water for tea, so the jury's still out on that one IMO. Some people would just say heat is heat, but without an actual test, IMO, that's an assumption.
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tealifehk
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Thu Jan 04, 2018 1:48 am

Also if you're anemic, you definitely would benefit from a tetsubin! That was a booboo on my part that I edited out after.

I think tetsubin would make green tea easier to drink, but you'd lose some of the health benefits while you were at it.
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CWarren
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Thu Jan 04, 2018 1:56 am

tealifehk wrote:
Thu Jan 04, 2018 1:41 am
There's nothing on whether different heat sources make a difference, though, so maybe your one-hour wait for water to boil isn't really doing anything :lol:
Most of the time my tetsubin is heated on infrared so usually closer to ten minutes waiting time but when I do have the luxury of using my charcoal stove the hour wait is well worth it for the primal experience alone. Playing with bamboo, olive pit and various Japanese charcoals just makes me feel good the same as hardwood grilling makes me feel good. If all it does is smell incredible and make me all kinds of happy than I’m good with it. I still feel it gives more body and added flavor but it could be in my head. I’m also okay with that delusion. :lol:

EDIT: also it’s closer to thirty minutes if I use a charcoal starter. Grin
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tealifehk
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Thu Jan 04, 2018 2:34 am

CWarren wrote:
Thu Jan 04, 2018 1:56 am
tealifehk wrote:
Thu Jan 04, 2018 1:41 am
There's nothing on whether different heat sources make a difference, though, so maybe your one-hour wait for water to boil isn't really doing anything :lol:
Most of the time my tetsubin is heated on infrared so usually closer to ten minutes waiting time but when I do have the luxury of using my charcoal stove the hour wait is well worth it for the primal experience alone. Playing with bamboo, olive pit and various Japanese charcoals just makes me feel good the same as hardwood grilling makes me feel good. If all it does is smell incredible and make me all kinds of happy than I’m good with it. I still feel it gives more body and added flavor but it could be in my head. I’m also okay with that delusion. :lol:

EDIT: also it’s closer to thirty minutes if I use a charcoal starter. Grin
Charcoal starter very bad for qi! :shock:

All kidding aside, if you enjoy it, why the hell not, right? I switched to the Hario for convenience and because my Philips glass kettle has plastic on the inside of the lid. I wanna avoid using plastics in kettles wherever possible! Unfortunately it takes frigging forever for the Hario to boil compared to my electric kettles.

The iron contribution aspect alone means I'm going to use the ol' tetsu much more often with everything except fresh green tea!

One thing I just realized is that a tetsubin might affect huigan. I will have to try some of that Spring of Menghai with a tetsubin to see if there is a dampening effect from the tetsubin!
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CWarren
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Thu Jan 04, 2018 3:23 am

tealifehk wrote:
Thu Jan 04, 2018 2:34 am

Charcoal starter very bad for qi! :shock:
I use a cast iron Japanese starter over open flame with no other material than the charcoal so my qi is qi-riffic. :lol:

Also I stopped using my old glass kettle for the same reason, (plastic).

As for huigan because it often translates to sweetness and the iron tends to cater to that I can’t really speak about it unless it’s more than just the sweet throat/back of the mouth type huigan. Interesting thing to think about now though.
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tealifehk
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Thu Jan 04, 2018 3:50 am

Oh wow, I was thinking self lighting charcoal briquettes! That sounds like quite the setup you have going. It's possible the sweetness would be more apparent if bitterness was reduced, but IMO iron on its own doesn't make tea any sweeter; it is just reducing other components that might affect perceived sweetness. I thought huigan was tied into astringency and bitterness, but perhaps not!

I would love for someone to do a study on heating water with different energy sources. Current science says it wouldn't make one iota of difference, but I'd like to put it to the test! Unfortunately I don't have a charcoal stove, even though I can get one pretty cheap. Apartment dwelling is not conducive to using a charcoal stove! I suppose I could stick one outside the warehouse door and boil water in the hallway, although that is probably some kind of violation of the fire code here!

I'll have to leave the charcoal vs gas vs ceramic glass vs induction test to someone else! ;)
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tealifehk
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Thu Jan 04, 2018 5:24 am

IMO huigan is definitely tied to astringency and bitterness. The SoM is a huigan bomb so it'll be interesting to see what the tetsubin does for it!
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Youzi
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Sat Jan 30, 2021 4:38 pm

@tealifehk

old thread, but found this:
https://www.researchgate.net/publicatio ... ron_Kettle

Could be interesting if someone could get the full version.
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