The delicious way champagne bubbles tickle the tongue is based on how “soapy” wine is, according to new research.
Poured into a glass, not all soft drinks fizz the same way. Sparkling water creates a firework of bursting bubbles, bursting across the surface of a glass. The beer has bubbles that start in a line but quickly spread outward to clump together in seemingly random upward patterns.
But champagne is elegant. This creates a handful of bubbles that drift upwards in crisp straight lines, almost as if they’re being pumped down a treadmill by an invisible factory at the bottom of the flute.
So what makes champagne bubbles so pleasantly predictable?
Physicists from Brown University and the University of Toulouse in France have found the secret. Champagne, prosecco and other sparkling wines, they say, contain more soap-like compounds called surfactants.
In fact, these fatty acids seem to be part of what makes the drink so palatable.
“The theory is that in Champagne these contaminants that act like surfactants are the good stuff,” explain engineer Roberto Zenit, who studies fluid mechanics at Brown University.
“These protein molecules that give flavor and uniqueness to liquid are what make the chains of bubbles they produce stable.”
In experiments, researchers injected bubbles of nitrogen into different liquids and glasses using a series of specially shaped syringes.
By changing the size of the bubbles and the composition of the drink itself, the team created different bubbly patterns.
When the researchers added more surfactants to a lager, the unstable bubble chains became stable.
Even without surfactants, researchers could achieve this by enlarging the bubbles in beer. But no water. It didn’t matter how big the bubbles were in the water. Without surfactants, its bubbles always seemed to behave chaotically.
“These two experiments clearly indicate that there are two possibilities for stabilizing a chain of bubbles,” researchers conclude.
By running the numbers on density, surface tension and viscosity, they then figured out why.
A bubble rising in water, which has a low concentration of surfactants, creates a wake with two strands spinning in different directions. Each subsequent bubble is lifted in the opposite direction to its predecessor.
“Consequently, the bubbles are pushed laterally, resulting in increasing separation and deviation from the in-line configuration,” the researchers explain.
The image below shows this instability in action.
But when a liquid contains enough surfactants, the structure of a bubble’s wake changes so that the bubble behind it is drawn in line with the one before it.
How champagne fizzes may not seem like an urgent scientific question, but the knowledge is actually quite useful.
“We are interested in how these bubbles move and how they relate to industrial applications and in nature,” explain Zenith.
For example, now that scientists know that surfactants can alter the way bubbles rise, they can examine the chains of bubbles in just about any liquid and use this information to assess its level of surfactant contamination.
This could be particularly useful near deep-sea vents spouting methane and carbon dioxide, where direct sampling of materials is difficult, or for keeping tabs on vent tanks at processing facilities. ‘water.
The proof was in the prosecco all the time.
The study was published in Physical examination fluids.