Preventing Flat Soda
Name: Ben F.
I was once told that if you have a half full 2L bottle of
coke, and you squeeze the sides together to create less air in the
bottle, that the soda will not go flat as fast. I could understand how
this could work. I think it would have something to do with partial
pressure. My instinct tells me that there may be more to it than
that. So… What is the best way to keep my soda from going flat?
Quite the contrary. Squeezing the bottle as you described and then capping it
will produce a less than 1 atmosphere pressure condition inside the bottle
because the flexible container will try to return to its original shape. The
reduced pressure inside the squeezed bottle will encourage the carbonation to
be released from solution. This will make the soda go flat sooner.
To keep the soda from losing its fizz, it should be stored capped, cold and at
an elevated pressure. I purchased a cap that enables one to re-pressurize the
bottle. One screws it in place and then operates a little pump that is part of
and affixed to the center of the cap. I purchased mine at a Wal-Mart.
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Update: June 2012