07/30/2026
Which glass keeps Champagne fizzy the longest: a coupe or a flute? 🥂
Most people answer "the flute"—and they'd be right.
But the more interesting question is: why?
Most people assume it's because a flute "traps" the bubbles better than the wider coupe. That's not really what's happening.
If we approximate the two glasses as simple cones holding the same amount of Champagne, something surprising emerges from the geometry. The wide coupe exposes roughly four times more liquid surface area than the narrow flute.
So why does that matter?
Because most of the CO₂ doesn't leave Champagne as the bubbles you see. It leaves by molecular diffusion across the liquid surface. A larger exposed surface gives the dissolved CO₂ many more opportunities to escape into the air.
In fact, some measurements suggest that as much as 80% of the CO₂ loss comes from diffusion, with only about 20% coming from the visible bubbles.
In Field Notes #4, we walk through the science, show the geometry, and explain why the answer has much more to do with molecular physics than with the bubbles themselves.
📖 Read the full Field Note and see the geometry here:
https://perlagesystems.com/blogs/applied-fizzics-field-notes/field-notes-4
Applied Fizzics Field Notes is a weekly series exploring the physics behind Champagne, cocktails, carbonated beverages, and the surprising science hiding in everyday life.
Next week's Field Note question:
If you shake a can of beer, does tapping on the top really keep it from foaming over? 🍺
