Ask Onix
The art and science behind champagne bubbles
Over three and a half centuries of research into sparkling wines has uncovered the secrets to maximizing enjoyment-from glass shape to pouring technique and even the ambiance in which it's consumed.
How bubbles form in champagne
The effervescence in champagne stems from a meticulous double fermentation process. After the initial fermentation, a sweet yeast mixture is added to the wine, triggering a second fermentation known as prise de mousse, or "capturing the sparkle." As yeast consumes sugar, it releases carbon dioxide, saturating the liquid under pressure. The wine then ages for at least 15 months, often upside-down, allowing dead yeast cells to settle in the neck. These cells, or lees, release compounds that enrich the wine's flavor over time-non-vintage champagnes age for a minimum of 12 months, while premium vintages may mature for decades.
To remove the sediment, winemakers rotate the bottles, freeze the neck, and expel the yeast plug under pressure, preserving most of the carbonation. The result? A glass containing roughly a million bubbles, each playing a crucial role in aroma and taste.
The role of bubbles in flavor and aroma
Bubbles in sparkling wine range from 0.4mm to 4mm in diameter, influenced by sugar content, alcohol levels, and glass shape. Far from mere visual appeal, they act as vehicles for aromatic compounds. As bubbles rise and burst, they release a mist of chemicals that enhance the wine's bouquet. Research by physicist Gérard Liger-Belair at the University of Reims found that bubbles around 3.4mm in size maximize aroma evaporation. Chilling the wine further refines this effect by reducing the alcohol carried in each bubble, preventing it from overpowering delicate flavors.
Interestingly, the size of bubbles can even be heard-larger bubbles produce a deeper pitch when they pop, while smaller ones emit a higher tone. Though subtle, this auditory cue can distinguish between different sparkling wines.
Six science-backed tips for the perfect pour
1. Set the mood
Environment significantly impacts perception. Studies show that lighting and music alter how champagne tastes-classical music, for instance, has been linked to higher spending on wine compared to pop hits. A well-curated atmosphere can elevate the experience, while harsh lighting and loud music may detract from it.
2. Choose the right glass
The iconic coupe and flute each offer distinct advantages. While the wide, saucer-like coupe exudes luxury, the tall, narrow flute better preserves carbonation. Liger-Belair's research found that flutes promote better liquid mixing, releasing more aromatic compounds. Coupes, by contrast, create "dead zones" where fewer bubbles form, diluting the wine's intensity. Polystyrene cups, meanwhile, are the worst choice-bubbles cling to the sides, growing unnaturally large before bursting, disrupting the delicate mist of aromas.
3. Clean your glass-carefully
Overzealous cleaning can leave soap residue, interfering with bubble formation. Some enthusiasts avoid soap altogether, opting for water-only rinses. Glass manufacturers even etch the inside of flutes to encourage more bubbles to form.
4. Pour like a pro
Pouring champagne down the side of a tilted glass-known as the "beer pour" method-preserves more carbonation than a vertical pour, which causes turbulence and releases excess CO₂. This technique helps maintain the wine's effervescence and complexity.
5. Drink it sooner rather than later
Carbon dioxide gradually escapes through tiny pores in cork stoppers. Research shows that vintage champagne loses over half its fizz after 35 years and becomes nearly flat after 76. While most consumers won't notice this effect, collectors with aged bottles should take note.
6. Consider altitude
At high altitudes, such as on airplanes, low pressure and humidity dull the palate, making wines taste more acidic. Champagne, already high in acidity, is best enjoyed early in a flight before these effects intensify. In zero gravity, like on the International Space Station, fizzy drinks become a "foamy mess," as bubbles fail to rise properly.
A toast to science
As one group of scientists noted in a 2024 review, sparkling wine tasting is not just about glamour-it's a playground for chemists and physicists. From the fermentation process to the final sip, every detail contributes to the experience. So next time you raise a glass, remember: the perfect pour is a blend of art, science, and a little bit of patience.
