Does tapping a can actually reduce fizz?

I don’t see how agitating the can anymore would make it less likely to fizz over.

I never got that. You would think it would be more fizzy! It never worked for me.

I think , if anything, it would fizz things up more.

I use the tap on the bottom of the can, and yes, it works.

But whats the science behind it? It doesn’t make any sense to me :P

I have no idea how it works. We were juvenile beer drinkers growing up, so we had to use it a lot.

It pushes all the bubbles up to the top of the can, so when you open the drink all the gas can come out rather than gas forcing up the liquid that was above it…

The How Stuff Works website attempts to explain it:

When you shake a soda can, some of the gas comes out of solution. There are a bunch of carbon dioxide bubbles clinging to the inside of the can, trying to get out. When you open this can and the gas rises to escape, it doesn’t only push on the liquid at the very top of the can. Because gas bubbles are stuck to the top, sides and bottom of the can, they force all of the liquid out because all of the liquid is blocking their upward path.

When you tap on the can, you knock bubbles off the bottom and sides of the can, at which point they rise to the top (because gas is lighter than liquid) and there is only a small amount of liquid blocking their escape when you open the can.

The more the drink disturbed, the more gas gonna come out from it. For example the Coca-Cola products are made so, if you pour out a glass of beverage from any container (can, bottle, tap, etc), when you ready to drink it, it has to contain 3g/liter CO2. that’s why the can has more CO2/liter (I think 10g/liter), then a 0.5l bottle, because the flow of the beverage is so disturbed when you serve that it loses many bubbles on the way out.

Straight Dope covered this one, too. The best they could come up with is that tapping the can delayed you from opening it long enough to let the carbonation settle down.

Thanks everyone!!

Makes perfect sense! The amount of fizzing catalyst (the CO2) doesn’t change, just it’s position in the can! Cool beans.

There is NO bubbles when the can has not been opened!

@simone54, I suggest you find a clear bottle of Coca-Cola (or beer or whatever) and shake it up. Then let us know what you observe.

Yes. No bubbles.