As kids, we always thought it was a pretty funny joke to shake up a bottle of soda and leave it for the next unsuspecting person. Our sense of humor has improved since then, happily - and we've gotten a lot more curious! Why does shaking fizzy drinks make them even fizzier? And more importantly, once shaken, how can we avoid getting a shower?
Carbonated drinks are made by forcing carbon gas into a beverage under pressure. In an unopened bottle, there is an equilibrium between the carbon that has been dissolved into the liquid and the carbon gas floating at the very top of the bottle. Opening the bottle results in a bit of fizzing as the pressure that has been keeping the carbon dissolved is released, but nothing that will spray you in the face with soda.
If you shake the bottle before opening it, some of the carbon that has been floating at the top of the bottle gets suspended in the liquid. This "extra" carbonation stays in larger (though not necessarily visible) bubbles than the already-dissolved carbon. If you or your innocent friend open the bottle at this point, the large bubbles will rise very quickly to the liquid's surface - resulting in an impressive soda explosion!
If you know that your soda has either accidentally or intentionally been shaken, just let it sit for a little while before opening. Those large bubbles of extra carbonation will eventually work their way out of the beverage and back to the top of the bottle where they belong.
Related: Good Product: Soda Siphon for Homemade Fizzy Water
(Image: Flickr member vox_efx licensed under Creative Commons)
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Comments (6)
Why do things like mineral water, seltzer and tonic water seem to explode at any given moment, even if the bottles have not been shaken?
I don't drink soda, but I do use a lot of soda water for drinks. It doesn't matter how long the bottle has sat around, it ALWAYS explodes on me. Maybe they hyper-carbonate soda water? It's very frustrating.
- Amelia of Gradually Greener
Yes, Soda Water ALWAYS explodes!
Why do people tap the top of their soda can? Does it actually help?
Katiwalker - I always tap the top of the soda can before I open it. I must admit, I don't know if actually works, but I've never had any explosions.
Someone told me about the tapping trick a long time ago. I have tapped the tops of soda cans ever since and have never had one explode on me. I have no idea why, but it seems to work.
The can tapping thing was shown on Food Detectives with Ted Allen but he also showed it on bottles and it worked! I buy those sparkling water beverages you get at the grocery store near the seltzer. Those have a tendency to explode almost as bad as seltzer and I've actually remembered this trick a few times. Sure enough, it actually does help. I've found I need to tap it a few times to let the bubbles fly up to the top and then if it looks like it might blow when I start opening, I tap it again a few more times.