Cracking Open the Mystery of How Many Bubbles Are in a Glass of Beer (acs.org) 34
After pouring beer into a glass, streams of little bubbles appear and start to rise, forming a foamy head. As the bubbles burst, the released carbon dioxide gas imparts the beverage's desirable tang. But just how many bubbles are in that drink? The American Chemical Society: By examining various factors, researchers reporting in ACS Omega estimate between 200,000 and nearly 2 million of these tiny spheres can form in a gently poured lager. Worldwide, beer is one of the most popular alcoholic beverages. Lightly flavored lagers, which are especially well-liked, are produced through a cool fermentation process, converting the sugars in malted grains to alcohol and carbon dioxide. During commercial packaging, more carbonation can be added to get a desired level of fizziness. That's why bottles and cans of beer hiss when opened and release micrometer-wide bubbles when poured into a mug.
These bubbles are important sensory elements of beer tasting, similar to sparkling wines, because they transport flavor and scent compounds. The carbonation also can tickle the drinker's nose. Gerard Liger-Belair had previously determined that about 1 million bubbles form in a flute of champagne, but scientists don't know the number created and released by beer before it's flat. So, Liger-Belair and Clara Cilindre wanted to find out. The researchers first measured the amount of carbon dioxide dissolved in a commercial lager just after pouring it into a tilted glass, such as a server would do to reduce its surface foam. Next, using this value and a standard tasting temperature of 42 F, they calculated that dissolved gas would spontaneously aggregate to form streams of bubbles wherever crevices and cavities in the glass were more than 1.4 um-wide. Then, high-speed photographs showed that the bubbles grew in volume as they floated to the surface, capturing and transporting additional dissolved gas to the air above the drink. As the remaining gas concentration decreased, the bubbling would eventually cease. The researchers estimated there could be between 200,000 and 2 million bubbles released before a half-pint of lager would go flat.
These bubbles are important sensory elements of beer tasting, similar to sparkling wines, because they transport flavor and scent compounds. The carbonation also can tickle the drinker's nose. Gerard Liger-Belair had previously determined that about 1 million bubbles form in a flute of champagne, but scientists don't know the number created and released by beer before it's flat. So, Liger-Belair and Clara Cilindre wanted to find out. The researchers first measured the amount of carbon dioxide dissolved in a commercial lager just after pouring it into a tilted glass, such as a server would do to reduce its surface foam. Next, using this value and a standard tasting temperature of 42 F, they calculated that dissolved gas would spontaneously aggregate to form streams of bubbles wherever crevices and cavities in the glass were more than 1.4 um-wide. Then, high-speed photographs showed that the bubbles grew in volume as they floated to the surface, capturing and transporting additional dissolved gas to the air above the drink. As the remaining gas concentration decreased, the bubbling would eventually cease. The researchers estimated there could be between 200,000 and 2 million bubbles released before a half-pint of lager would go flat.
Peer review required (Score:2)
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Guiness has negative bubbles, that's why they go down.
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they go down at the outside and up in the middle, now if we just substitute space-time for bubbles we might have a kind of warp drive
Guiness bubbles go down (Score:5, Informative)
https://www.rsc.org/news-event... [rsc.org]
It is a mystery that has confounded many a pub-goer. Locals testify to the fact that bubbles in their booze always go up, with one exception.
The Royal Society of Chemistry has finally solved the puzzle why Guinness bubbles break the rule by going down - yet still end up at the head.
In a lunchtime recreation, members of the RSC followed the perfect method of pouring a can of Guinness and watched it begin to settle while noting the reaction. When the bubbles touch the glass they experience drag, as happens when a finger is slid along the surface. At the centre of the glass, the bubbles are free to rise rapidly, as they naturally do in a liquid, creating a circulation.
The bubbles push and pull the surrounding liquid with them by the time they reach the creamy head. At the top, this liquid flowing upwards hits the surface and flows outwards towards the glass edge, which pushes the current down. As the flow moves downwards in waves, it pushes and pulls the bubbles that are hanging around at the glass edge pulling them down. More bubbles flow up at the centre and the circulation continues...
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https://web.stanford.edu/group... [stanford.edu]
Seems that same dynamic can be seen in most liquids, including any other beer.
Ryan Fenton
Animal testing, fine - but beer testing? (Score:2)
While many animals are specially raised, then tested with and killed for the sake of human safety testing, saving many human lives...
I don't know how comfortable the average person would be knowing how many beers must have been sacrificed for this study.
Ryan Fenton
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>I chug a beer every time I see your name.
I only post about a few times a week.... so that's quite reasonable.
Ryan Fenton
Let's find out... (Score:3)
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jeez dude, how old are you?
seeing as how I got the reference, as least as old as me lol
I always associate the ad/owl w/ Conjuntion Junction... all these memories bubbling up to the surface
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Do you really have to be old to get that reference? They're still airing that commercial (albeit the 15s version, not the full 60s one).
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no kidding, the same one from way back then? can't be too many examples of that happening
I remember as a littl'un thinking the owl cheated by just biting in to it; and I haven't stopped collecting whooshes ever since
The important question (Score:2)
How smooth or course should the interior of my beer mug be to obtain the 'optimal' amount of effervescence?
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How smooth or course should the interior of my beer mug be to obtain the 'optimal' amount of effervescence?
Ironically enough, a bartender once told me you could tell if a glass was clean or not by the bubbles.
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How smooth or course
coarse [cambridge.org]
should the interior of my beer mug be to obtain the 'optimal' amount of effervescence?
You're probably going to want several different beer mugs, as the answer to that question depends on how fast you drink your beer - and if you're anything like me the first one doesn't last very long at all...
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DO YOUR DILIGENCE (Score:2)
Three Cheers for Science! (Score:5, Funny)
(Reading the budget justification for this program)"Researchers, using a value and a standard tasting temperature of 42 F, will calculate that dissolved gas will spontaneously aggregate to form streams of bubbles wherever crevices and cavities in the glass were more than 1.4 um-wide. Then, using high-speed photography, researchers will show that the bubbles grew in volume as they floated to the surface, capturing and transporting additional dissolved gas to the air above the drink."
(The Rest of Us) "I can't believe that shit actually worked. You got PAID, to do that?"
(Researchers) "Hellz yeah we did. (clink) Here's to research!"
Um, thanks? (Score:3)
That's why bottles and cans of beer hiss when opened and release micrometer-wide bubbles when poured into a mug.
I guess that's for the one person who's never opened a carbonated beverage --
but has used electricity, a computer and the Internet to read that.
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most 4 year olds?
No, No, No... (Score:2)
This was first done by a Young Einstein. Who was actually Australian, in case you didn't know.
This [youtube.com] is what happened.
Shitty research. (Score:2)
Pretentious "white glove" research that only benefits the beer industry trying to maximize profits by fine tuning sensory appeal.
The real questions and the true unsung heroes of this are the lowly post-docs and unfunded junior faculty who are tasked with understanding what happens to those bubbles at the far end of the alimentary canal.
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https://shop.3dfilaprint.com/b... [3dfilaprint.com]
Like Champagne (Score:2)
The cheaper and rougher the glass, the more bubbles.
And the exact number is important because... (Score:2)
Just because, I guess
And how many beer atoms were split? (Score:2)
Just how many beer atoms did they need to split in order to figure out this mystery? (anyone who doesn't get the reference should Google "split beer atom" :)
I saw this movie! (Score:2)
Back in 1988! [imdb.com] Finally! Vindication for Mr. Serious!
I'd consider this "harmful science". (Score:2)
Because it took time from other, more valuable things, that could have been researched.
Things I'd be interested in knowing (Score:2)
1. What fraction of the original CO2 came out in bubbles, vs out gassing from the surface or staying dissolved (latter can be determined from Henry's law)?
2. Did they try different grades of glass cleanliness?
3. Different beers? Guinness I would assume would have more bubbles, but how much of Guinness bubbles are CO2?
4. Did drinking the beer increase bubbling rate?
5. How much of the original CO2 ended up in the head (for standard tilted pour)?
Inquiring mind(s) want to know!
Which middle school? (Score:2)
Which middle school did this project? That was a good way for seventh graders to learn how to do experiments.
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