big question about boiling water

[Fireflower]

i just need to understand better a thing.
usually i use to warm up water until 70°c (for green teas) and then i pour the water to the kyusu.
my doubt is if is better to boil the water and then to wait until the temeprature cool down to 70° c

which way is right?

[Xell]

Boil it first, most likely you will even notice slight change in taste.

[kaminix]

Boil it first, most likely you will even notice slight change in taste.

I've heard this elsewhere too, but why is that?

Dead water is dead, from what I've heard, because it has been deoxygenated from the boiling; so unless one wants dead water this suggests that not bringing the water to a full boil would be beneficial as there might be more oxygen left in the water, no?

[Xell]

I didn't research this myself, but i believe, that boiling reduces those elements in water, that can react with green tea and change its taste. For example minerals

[kaminix]

Hm, I've heard that explanation before but I don't really see how that would work. Evapourating minerals seems hard and and I don't think you can dissolve it in water vapour.

[Xell]

Hm, I've heard that explanation before but I don't really see how that would work. Evapourating minerals seems hard and and I don't think you can dissolve it in water vapour.

Not evaporating, but it will be left in boiling pot as residue. Like that white, stone like stuff on walls. (sorry, can't explain properly with level of my english )

[kaminix]

Hm, I've heard that explanation before but I don't really see how that would work. Evapourating minerals seems hard and and I don't think you can dissolve it in water vapour.

Not evaporating, but it will be left in boiling pot as residue. Like that white, stone like stuff on walls. (sorry, can't explain properly with level of my english )

Hm, I suppose that's possible. But that would mean it reacts with something in the water right? Other minerals?

[Xell]

Hm, I suppose that's possible. But that would mean it reacts with something in the water right? Other minerals?

Now i'm little confused myself, why taste is changing, minerals won't go away completely, only some part will drop or stick to walls. And also i heard somewhere, that boiling water makes it alive, not opposite But one thing for sure, green tea will taste bad when hard water is used.

[Chip]

However if you use a filter, this is largely a non issue since scale is largely removed.

I boil and use a yuzamashi (water cooler) and warming the pot to bring the temp to where I want it. I actually boil a full electric kettle, which is enough for around 5 steeps. This remains warm enough to go through all 5 steeps. This is for greens however.

[entropyembrace]

From what I understand boiling first and letting the water cool is the traditional method and the reason behind this is that before modern water treatment systems were developed water often wasn´t safe to drink until after it was boiled fully. In many places this is still true so the practice continues often with good reason.

But for us on teachat I´m pretty sure all or most of us have access to clean water...if not from the tap in the form of bottled water. so it´s not really necessary unless you want to boil off the chlorine (which has a lower boiling point than water) from your tap water...but a good filter would probably work better.

[Chip]

From what I understand boiling first and letting the water cool is the traditional method and the reason behind this is that before modern water treatment systems were developed water often wasn´t safe to drink until after it was boiled fully. In many places this is still true so the practice continues often with good reason.

But for us on teachat I´m pretty sure all or most of us have access to clean water...if not from the tap in the form of bottled water. so it´s not really necessary unless you want to boil off the chlorine (which has a lower boiling point than water) from your tap water...but a good filter would probably work better.

I do it because this allows me to preheat my wares, and not have to reheat for 5 steeps ... for greens. I am guessing I like the methodology since I have no inclination to get a Zoji or similar.

I don't get too hung up on water nor its heating.

[Marco]

Yes me too thought that it is from those old times when water quality wasn't always this good.
But a friend of mine was told by a Japanese teamaster to let the water boil for 1-2 minutes before cooling down and using for brewing tea. I do not know the reason but he insisted not to stop imediately at boiling point.
So I wonder why.

[iannon]

Time honored tradition perhaps? I was thinking another reason outside of water quality issues is that in the old times the teamaster got good at hitting the boiling point temp and then knowing how long it took to cool to their desired usable temps?

[teaisme]

let the water boil for 1-2 minutes before cooling down and using for brewing tea.

That is what I have been told as well when brewing oolong.

When it comes to japanese greens, I have had great pots with both water not boiled and water boiled, its pretty hard for me to tell the difference

water that has been boiled for too long is noticeably worse for me though

[tortoise]

I boil it first because, like Iannon said, I know how to hit my mark from that point for sencha -- which is what I drink mostly. I don't let the water boil for long though. As soon as it starts to boil well, I pull it off. I think if one is concerned about losing oxygen, just don't boil the water for very long.

I don't know if boiling changes mineral content, but I doubt it. I don't think that is really important unless your water source contains minerals that are bad. Lead. Arsenic. etc. In that case, you'd want a different water source and boiling wouldn't help enough.