[_Stefan_ (OP)]

I put a plastic 2L bottle of fruit juice in the freezer for a day or so. The bottle is the kind that has the air completely removed and then sealed with a foil which needs to be peeled off in order to open the bottle. The effect is that the liquid fills the entire bottle, but as soon as you unpeel the foil it drops down to its normal volume some way down the neck. The liquid also doesn't move if you shake it before you break the seal.
Well, the liquid did not freeze at all. So I took it out of the freezer and peeled off the foil seal. As soon as I did this, the liquid began to freeze, from the top of the bottle gradually down to the bottom.

Why is this? Is it something to do with the pressure inside the bottle? The vacuum effect doesn't allow the molecules in the liquid to move around and align themselves to suitably form ice crystals?

[Bored chemist]

Looks to me like a case of supercooling.
http://en.wikipedia.org/wiki/Supercooling

[_Stefan_ (OP)]

Thanks!

Watching it freeze certainly made my day yesterday

[lyner]

Could it be connected with a slight change of pressure when you remove the seal?

[healthyju]

   
Thanks for letting me join this group so interesting.....   
It really is very curious what happens? they do not understand, I would like to share an experience with  (ADVERTISING  LINK REMOVED Mod) I discovered them on a trip to Costa Rica, a beautiful tropical country where they have juices drinks all day long, all year long. My favorite one I tried there was the Mango juice. For those of you who haven’t heard from it, mango is a deliciously sweet orange yellowy tropical fruit.

[Madidus_Scientia]

sigh

[Chemistry4me]

ψ?

[Raghavendra]

purrr! []ha ha

[Chemistry4me]

I know!  []

*ψ*

[Raghavendra]

ok