# Why does soda fizz down faster with your finger in it?
**URL:** https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523
**Category:** Factual Questions
**Created:** [April 17, 2000, 7:59am UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523 "2000-04-17T07:59:00Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@JJ\_Richard](https://boards.straightdope.com/u/JJ_Richard)
#### Post date: [April 17, 2000, 7:59am UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/1 "2000-04-17T07:59:00Z")
Ok, I sent this question to Cecil, and got an “automated” reply from Jill advising me to put it to the “teem” here first…so, here goes.
I’m 35. My daughter is 13. The other day she showed me that if she put her finger into the fizz of a freshly poured cup of soda, that the soda will “fizz down” (dissipate) faster.
Silly me, waiting for my sodas to “fizz down” at the natural rate my whole life, and she figures out a better way at age 13.
Of course, her first question: why? Hmmm.
Hmmm indeed. My first thought was that perhaps it is the salt from the human skin chemically interacting with the “fizz” bubbles, and somehow creating this “fizz shockwave”.
So, I poured a new cup of soda (into a new cup), and added some table salt to the fizz. No joy. No reaction whatsoever.
Then, I figured that perhaps it is the heat from the finger that sparks the “shockwave” (you know, heat makes the bubbles expand, blah blah)…
So, I heated up the fat end of a butter knife and stuck it into yet another freshly poured cup of soda fizz. No joy.
Having my mental sleeves now rolled up, I conducted the following “experiments”, which ultimately gained zero ground as far as an explanation goes, but perhaps did serve to identify at least some of the variables of the equation. Here’s what I found…
The “fizz” dissipates faster WITH a finger poked in it:
1. Regardless of whether it’s poured FROM a 2 liter bottle or a 12 oz. can.
2. Regardless of whether it’s poured INTO a cup of plastic or of glass.
3. Regardless of whether it’s “regular” or “diet” soda (although I think it’s more aggresive in diet).
4. Regardless of whether or not ice cubes are present in the cup prior to pouring.
One interesting thing that I have noticed, however…if I pour a cup of soda into cup “A”, and then “finger” it (to speed up the de-fizz), any subsequent pours of soda back into cup “A” de-fizz at the ACCELERATED rate…regardless of whether I “re-finger” it or not! ??
Ok, “teem”, what’s the scoop? 🙂
JJ Richard
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### Author:  [@TheMadHun](https://boards.straightdope.com/u/TheMadHun)
#### Post date: [April 17, 2000, 8:05am UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/2 "2000-04-17T08:05:00Z")
I seem to remember a column dealing with this…the conclusion being that the oil from your skin is what causes the rapid dissipation of bubbles. I’ll try to find it.
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### Author:  [@GaWd](https://boards.straightdope.com/u/GaWd)
#### Post date: [April 17, 2000, 8:36am UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/3 "2000-04-17T08:36:00Z")
It’s actually the oils on your skin. No articles, don’t really wish to research it.
I actually discovered this at(of all places), a CSU Chico kegger! I was standing there staring at my over headed beer, and my friend who’d been living there for like 2 quarters(and subsequently flunked out after 5 years, big surprise…), takes his finger and wipes his face with a finger, and swirls it in his beer.
Lo and behold!! the head died off rapidly, and we enjoyed our beers happily ever-after.
🙂
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### Author:  [@ticker](https://boards.straightdope.com/u/ticker)
#### Post date: [April 17, 2000, 9:10am UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/4 "2000-04-17T09:10:00Z")
You have heard of the saying _…pour oil on troubled water_?
I would guess adding salt would have the opposite effect. I remember as kids we delighted in adding sugar to coke to watch it fizz over the sides. Then we used to drink it! Yeauch!!!
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### Author:  [@waterj2](https://boards.straightdope.com/u/waterj2)
#### Post date: [April 17, 2000, 9:33am UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/5 "2000-04-17T09:33:00Z")
I just saw people doing this for the first time last night. I was wondering about it myself. It didn’t really seem to help all that much, though, but I wasn’t paying all that much attention.
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### Author:  [@Tomcat](https://boards.straightdope.com/u/Tomcat)
#### Post date: [April 17, 2000, 12:04pm UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/6 "2000-04-17T12:04:00Z")
All my drinking days I used the “rub-a-finger-on-the-side-of-your-nose-and-touch-the-foam” trick…Worked great in the States, but for some strange reason, it doesn’t work on Czech Beer. Really! Figure that one out…
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### Author:  [@handy](https://boards.straightdope.com/u/handy)
#### Post date: [April 17, 2000, 2:48pm UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/7 "2000-04-17T14:48:00Z")
Yeah! They all got it right, it used to be a beer question.
Just to check, I washed my hands & tried it and the foam didn’t change!.. Thus, people with filthy dirty grummy fingers have the most success but not with my drink.
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### Author:  [@emarkp](https://boards.straightdope.com/u/emarkp)
#### Post date: [April 17, 2000, 9:13pm UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/8 "2000-04-17T21:13:00Z")
Of course, the alternative is to tilt the glass and put the edge of the glass against the spout you’re pouring out of. This results in near-zero head. (For cans, just get as close as you can.)
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### Author:  [@cmkeller](https://boards.straightdope.com/u/cmkeller)
#### Post date: [April 17, 2000, 9:24pm UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/9 "2000-04-17T21:24:00Z")
The reason soda fizzes more when you add something solid to it, be it a finger, salt or ice, is because you’re supplying **nucleation sites** for the carbon dioxide to be attracted to and form bubbles around.
* * *
Chaim Mattis Keller
[ckeller@kozmo.com](mailto:ckeller@kozmo.com)
“Sherlock Holmes once said that once you have eliminated the
impossible, whatever remains, however improbable, must be
the answer. I, however, do not like to eliminate the impossible.
The impossible often has a kind of integrity to it that the merely improbable lacks.”
– Douglas Adams’s Dirk Gently, Holistic Detective
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### Author:  [@Squee](https://boards.straightdope.com/u/Squee)
#### Post date: [April 17, 2000, 9:44pm UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/10 "2000-04-17T21:44:00Z")
For those interested in the old GQ thread…
{url=http://boards.straightdope.com/ubb/Forum3/HTML/006497.html]Quickly reducing foam in a glass of soda
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### Author:  [@Squee](https://boards.straightdope.com/u/Squee)
#### Post date: [April 17, 2000, 9:46pm UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/11 "2000-04-17T21:46:00Z")
Dammit! Here: [Quickly reducing foam in a glass of soda](http://boards.straightdope.com/ubb/Forum3/HTML/006497.html)
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### Author:  [@Sofa\_King](https://boards.straightdope.com/u/Sofa_King)
#### Post date: [April 17, 2000, 9:46pm UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/12 "2000-04-17T21:46:00Z")
Um, when it comes to beer, earwax works the fastest. Or maybe there’s just a greater concentration of oils in the ear.
Please do not ask me what method of trial and error I used to come to this fascinating conclusion.
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### Author:  [@handy](https://boards.straightdope.com/u/handy)
#### Post date: [April 17, 2000, 11:14pm UTC](https://boards.straightdope.com/t/why-does-soda-fizz-down-faster-with-your-finger-in-it/10523/13 "2000-04-17T23:14:00Z")
Ah, just drink from a Waterford glass. They are so perfectly made, there is very little foaming.