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Name: Ben F.
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 2000

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.

ProfHoff 334

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