All good things come to an end. In the 1980s, the Champenois called time on the saucer-shaped coupe erroneously said to have been modeled on Marie Antoinette’s breast. Now they have decreed that the Champagne flute has to go. They want to reduce the world’s most famous wine’s association with celebration and move it into the all-kinds-of-occasions category. And since the flute signals ‘special occasion’ like nothing else, it needs to be replaced.
This isn’t simply a marketing issue. New research from the University of Reims has demonstrated that the flute is also a killer of bubbles, one of the wine’s most attractive aspects. Professor Gérard Liger-Belair, a chemical physicist, demonstrated why at a ‘virtual’ Champagne tasting in Reims in October.
Bubble science
The foam itself is created by the Prise de Mousse during secondary fermentation. Once the wine is sealed into the bottle with sugar and yeast, the yeast begins to consume the sugar, forming ethanol and the oxide of carbon. “Because the bottle is hermetically sealed, the CO2 is trapped inside the bottle and dissolves into the liquid,” he explained, noting that 24g per litre of sugar will produce 9g of CO2. “As the fermentation reaches 12°C, the pressure rises to six bars – meaning the pressure is six times the atmospheric pressure,” he continued. If the glass isn’t thick enough, the bottle will explode.
So far, so well known. But then Professor Liger-Belair showed a film of a bottle being opened, taken at 12,000 frames a second. As the CO2 is released from the bottle, it erupts in an explosion of carbonic ice. This is a process known as adiabatic expansion: as the gas decompresses, its temperature drops – a bottle chilled to 10°C will produce a cloud of CO2 that’s around -80°C. But the gas stabilizes within a fraction of a second, so the process can’t be seen with the naked eye.
Next, the Champagne is poured. “When you pour Champagne into the glass, you make a lot of turbulence,” explained Liger-Belair, showing a picture of the movement inside the glass. The swirls look like they come from Van Gogh’s painting Starry Night. “If you want to preserve a little more CO2 during the process, you have to tilt the glass, so there is less turbulence.”
But here’s the flute problem – the higher the glass, the greater the turbulence, because the wine has further to travel. “Surface area matters a lot,” he said. Change the shape of the glass, and there will be more or fewer bubbles.
The dust particles on the glass walls are also important. “Dust is not dirt,” said Professor Liger-Belair, showing a film of how dust particles, which are hollow, attract the CO2 in the liquid. As the CO2 is pulled through the gas cavity, it breaks into two. One part becomes a bubble, while the other remains trapped until it can go through the next cycle. “If you use a perfectly clean glass, the Champagne will be unable to produce bubbles.” As the bubbles rise through the liquid, they accumulate CO2 and volatile compounds, and grow in size. When they reach the surface and burst – or nucleate – they release the aroma compounds. The size of the bubbles, said the professor, say nothing about quality, but more about how much dissolved CO2 is in the wine – a result of how it was carbonated in the first place – and about the shape of the glass. “The main parameter isn’t the wine, but the glass. The taller the glass, the bigger the bubble.” But those big bubbles come at the price of the wine losing its CO2 faster. Flutes mean flat wine.
Tilting towards perfection
Professor Liger-Belair has entered into a glassware discussion with Hervé Fort, director of the famed Domaine Les Crayères restaurant in Reims, as well as with Philippe Jamesse, the head sommelier. They have created a tilted “Synergy” glass, designed to capture the maximum number of both CO2 and aroma molecules.
The glass, it has to be said, takes a bit of getting used to, not least because it looks like a concrete mixer. Using it feels like drinking from an enclosed soup ladle because the stem has to be held crossways. But it’s certainly striking and based on solid scientific research, and is planned to be released in early 2018 – approximately two decades before the experts will come up with an even better idea.
