“I only drink champagne on two occasions: when I’m in love and when I’m not in love!” Coco Chanel is said to have once said. So always. Champagne as an everyday drink is rather unthinkable for most “normal” drinkers. Champagne still stands for luxury, for something special. Accordingly, the corks tend to pop when it’s supposed to be festive. The fact that the cork can pop at all is due to the millions of bubbles in the bottle. Without her, champagne wouldn’t be champagne.
First, wine is made from the Champagne grapes, and sugar and yeast are added. The bottles are then stored upside down and rotated around their own axis once a day. The movement supports the fermentation process, while the carbonic acid is created. Nothing really special if the bubbles didn’t behave any differently than in other carbonated drinks.
The physicist Roberto Zenit from Brown University took a closer look into the champagne glass and found that the carbon dioxide bubbles do not “compete” with each other as they rise, as in other drinks, i.e. collide in the suction and rise in parallel, but rather are well-ordered in a stable vertical column. “If you know something about the dynamics of soap bubbles, that’s not normal, so of course we were immediately fascinated,” Zenit told Ars.
The researchers around Zenit set about experimenting. To do this, they not only looked at the hydrodynamic interactions in champagne, they also compared them with Pellegrino water, Tecate beer and a Brut sparkling wine from Spain. They found out that it is the surfactants that make the difference. They wrap themselves around the bubbles, which changes the hydrodynamic interaction. Surfactant molecules, mainly fatty acids, provide the flavor of the champagne. The scientists also found that the size of the bubbles also plays a role.
“It’s not magic. The surfactant molecules in champagne have two sides,” explains Zenit. “One side likes air, the other likes water, so one side of the molecule attaches to air and the other to liquid.” These molecules are not found in other carbonated drinks. The results were published in the journal Physical Review Fluids.
Previously, scientists from the Sorbonne University, among others, had already made champagne their subject of research. They wanted to research the mechanism responsible for the champagne’s crackling noise and found that the bursting of the bubbles plays a role in the rise. Because part of them is still underwater, the bursting causes an acoustic vibration. The strength depends on the amount of gas in the bubble and the size of the hole.
Sources: Physical Review Fluids, Ars
