Boffins conduct study - on why peanuts dance around in beer
- 10 months ago
Boffins have conducted a study - on why peanuts dance around in beer.
Researchers noticed that the bar snacks would move up and down within the glass in many repeating cycles.
They set about proposing a physical description of this "dancing peanuts spectacle".
The international team taking on the research comprised of academics from Durham University, Ludwig-Maximilians-University of Munich and University of Geneva.
Results published in the journal Royal Society Open Science suggest that as the peanuts descend into the beer, air bubbles within the liquid attach to the peanuts, causing them to become buoyant.
When the peanuts rise to the surface of the beer, the bubbles pop and the peanuts lose their buoyancy.
The researchers say: "In Argentina, some people add peanuts to their beer. Once immersed, the peanuts initially sink part way down into the beer before bubbles nucleate and grow on the peanut surfaces and remain attached.
"We used laboratory experiments and calculations to support this description, including constraint of the densities and wetting properties of the beer–gas–peanut system.
"We draw analogies between this peanut dance cyclicity and industrial and natural processes of wide interest, ultimately concluding that this bar-side phenomenon can be a vehicle for understanding more complex, applied systems of general interest and utility."
"Clearly then, the conclusion is that the period of the dancing motion is sensitive to the nucleation rate, to the detachment rate at the upper surface, and to bubble sizes on the peanuts, which in turn will be different in different beer varieties.
"Similarly, different peanut types—salted, roasted, shelled, etc.—could have substantial controls on the dynamics via changes in wettability or density.
"We survey some similar systems in silicate glasses and magmas. Dynamic similarities between beer and natural silicates have been proposed previously: Manga proposed a key similarity between bubble-bearing magma dynamics and bubbles in Guinness.
"Therefore, we close by proposing that this study has heritage and that the observation of bubble dynamics in beer is a rich topic, worth repeated investigation."
Researchers noticed that the bar snacks would move up and down within the glass in many repeating cycles.
They set about proposing a physical description of this "dancing peanuts spectacle".
The international team taking on the research comprised of academics from Durham University, Ludwig-Maximilians-University of Munich and University of Geneva.
Results published in the journal Royal Society Open Science suggest that as the peanuts descend into the beer, air bubbles within the liquid attach to the peanuts, causing them to become buoyant.
When the peanuts rise to the surface of the beer, the bubbles pop and the peanuts lose their buoyancy.
The researchers say: "In Argentina, some people add peanuts to their beer. Once immersed, the peanuts initially sink part way down into the beer before bubbles nucleate and grow on the peanut surfaces and remain attached.
"We used laboratory experiments and calculations to support this description, including constraint of the densities and wetting properties of the beer–gas–peanut system.
"We draw analogies between this peanut dance cyclicity and industrial and natural processes of wide interest, ultimately concluding that this bar-side phenomenon can be a vehicle for understanding more complex, applied systems of general interest and utility."
"Clearly then, the conclusion is that the period of the dancing motion is sensitive to the nucleation rate, to the detachment rate at the upper surface, and to bubble sizes on the peanuts, which in turn will be different in different beer varieties.
"Similarly, different peanut types—salted, roasted, shelled, etc.—could have substantial controls on the dynamics via changes in wettability or density.
"We survey some similar systems in silicate glasses and magmas. Dynamic similarities between beer and natural silicates have been proposed previously: Manga proposed a key similarity between bubble-bearing magma dynamics and bubbles in Guinness.
"Therefore, we close by proposing that this study has heritage and that the observation of bubble dynamics in beer is a rich topic, worth repeated investigation."