Finally Solved: The Mystery of Why Champagne Bubbles Rise Directly

From the pop of its cork to its delicate golden hue, champagne has many characteristics that make it a festive drink - but none as recognizable as its sparkling end.

Now researchers have shed new light on the quintessential sparkle, revealing why champagne bubbles rise in a straight line, unlike many other drinks.

“Our intuition, from studying the dynamics of bubbles, is that bubbles that rise in a line do not follow a straight line. The wake behind each bubble knocks the rear bubble to the side,” said study co-author Professor Roberto Zeni from Brown University, Rhode Island, USA.

But, he added, this is not the case for champagne and some types of beer.

According to Zeni, the trait unusual is due to particular ingredients in champagne which not only give it flavor but attach themselves to the bubbles, altering the motion of the fluid immediately behind them as they rise and thus allowing the bubbles to form a chain.

"These molecules, which attach to the surface of the bubble, induce changes in the wake which, in turn, prevent the bubbles from being removed from the pattern online,” Zeni said.

Writing in the journal Physical Review Fluids, Zeni and colleagues in the United States and France describe how they arrived at their conclusions by conducting a series of experiments in which nitrogen bubbles were introduced into a tank filled with a mixture of water and glycerin.

"These are false analogues of the champagne," Zeni said. The team varied both the size of the bubbles and the levels of detergent like chemicals in the mixture, called surfactants.

The results revealed that at As the bubble size increased, the bubbles began to form stable chains, meaning the bubbles passed through the fluid in a straight line. A similar effect was observed when the bubble size was held constant and the surfactant concentration was increased.

The team performed calculations to explore these effects, noting that whether the bubbles form a straight line depends on the twisting motion, or vorticity, created in the fluid behind a rising bubble.

While increasing the size of the bubbles may affect vorticity, allowing the formation of stable bubble chains, the fine champagne bubbles suggest a different mechanism is at play.

The authors say that the straight lines of tiny bubbles in champagne are due to the aromatic molecules, such as fatty acids, in the drink having surfactant properties.

When these molecules attach to the surface of a bubble , they modify its surface tension, making the bubble more deformable against forces acting at right angles to its movement but more rigid and "non-slip" against forces acting on a tangent.

"[Together, these effects] create more vorticity, which in turn helps change the nature of the wake that determines whether bubbles can stay in line,” Zeni said.

But it seems research isn't just helpful in explaining champagne curiosity.

"Understanding why bubbles rise in a line or disperse has important implications for other problems, such as industrial processes or natural phenomena," he said. declared.