Printed on the back of a box of tea bags from M&S...
Use only freshly boiled water as reboiled water has lost its oxygen.
Good lord. 🙄
Boiling water removes the dissolved oxygen from the water. This is different to the elemental oxygen that is contained within the water molecules.
Whether that makes a difference to the taste of the tea is another matter entirely.
Whether that makes a difference to the taste of the tea is another matter entirely.
Yes it does.
Additional oxygen can be in solution, as well as the oxygen bonded to the hydrogen. That's what fish breathe, and it's why you don't see bubbles of hydrogen coming out of every aquatic creature.
Printed on the back of a box of tea bags from M&S...
Use only freshly boiled water as reboiled water has lost its oxygen.
Good lord.
And ?
well, you learn something new every day.
And ?
Yes?
This is interesting. So why does the oxygen leave? When you look at the surface disruption of boiling water you could almost imagine more oxygen getting added
So why does the oxygen leave?
The heat drives it off. Hot water can't hold the same amount of oxygen in solution as does cold water.
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Because of the extra energy making everything move around more? That kind of makes sense
I guess reboiling might affect the ph level further, it's also going to concentrate minerals and contaminants such as nitrates further.
That could possibly affect the taste.
Scientists call it deaeriation. Nitrogen n stuff in there too. If you want to make clear ice for sculpture you boil it.
Water that has sat for a while is better as the chlorine smell goes away. Mineral water is salty, and hard English water is just crap.
What about water from an urn that is kept constantly (ish) hot?
Assuming that your water does boil at 100 degrees (which i understand it won't as its not distilled), from that graph, surely the water has no oxygen once its boiled the first time?
There is significantly more deuterium in water that has been boiled over and over.
Heavy, man.
if you were to use ionically filtered or Reverse Osmosis water then reoxygenate it you'd theoretically get a "fuller" flavour as you'd have stripped the water of impurities enabling you more molecular "room" for the tea extract.
surely the water has no oxygen once its boiled the first time?
That's why I questioned whether it would make any real world difference in my first post. 😉
Edit.
Boiling water also precipitates some soluble minerals into insoluble ones, which affects its composition. Hence limescale in kettles.
Also - the increased solubility of gasses in cold water is the reason why cold oceans are full of life - you'd expect it to be the other way round, but cold water holds more oxygen which helps the life.
I'll have H2O too
Boiling water removes the dissolved oxygen from the water.
So hang on. The instructions say, "Use only freshly boiled water as reboiled water has lost its oxygen." If the oxygen has been removed by the boiling process, what difference does it make whether it's freshly boiled or not? The horse has already bolted by that point.
The horse has already bolted by that point
Much like this point bolted an hour ago when mrjmt made it? 😀
Assuming that your water does boil at 100 degrees (which i understand it won't as its not distilled), from that graph, surely the water has no oxygen once its boiled the first time?
Bumcakes, I missed that. As you were, then.