# Why does meltwater taste different?

I've noticed that water obtained from melting ice cubes (by keeping them in the open) tastes different from water cooled to the same temperature.

Furthermore, the taste goes away if you keep it in the open for a sufficient duration of time.

I can think of these possible explanations:

• Dissolved gases being released
• Something to do with the crystal structure of ice
• Something to do with dissolved minerals

The Internet is giving me all sorts of varying answers.

Exactly what chemical differences exist between meltwater and cold water?

• I might guess the dissolved gases (and specifically the chlorine/chloramine) would be ejected faster from melted ice (and slowly from standing water), but I don't know if that's the taste you're looking for. – Nick T Jun 4 '12 at 3:25
• @NickT: I'm not looking for the taste, I'm looking for all the physical/chemical differences. The taste is just a point proving the existence of those differences. You can make that into an answer, though I'd prefer something more than a "guess" ;-) – ManishEarth Jun 4 '12 at 8:24

(not yet a fully grown answer: experiment still pending)

I heard that $\ce{CO2}$/$\ce{H2CO3}$/$\ce{HCO3-}$ is responsible for "fresh" taste of water.

@NickT: Chloramine has a very characteristic smell, so Manishearth could most probably tell us whether this was the smell/taste.

So, here are first questions for @Manishearth:

• does water that has been boiled and then cooled to the same temperature taste similar to the taste you're asking for?