Bubble physicist, Helen Czerski, reveals why you should care about the glass you are drinking your champagne from.
Helen Czerski: One of the things that is very irritating if you ever have to go shopping for things to fill a flat is there seem to be so many different types of wine glass. It's only a thing to drink wine out of, right? It's got sort of a stem, and it's got a flat bit and it's got a cup bit. How complicated does it need to be? And it turns out, in the case of champagne especially, the shape of the glass does matter quite a lot.
So to understand what shape a champagne glass should be, you, first of all, need to know what the glass is doing. At the bottom of the glass, there's something very important going on because that's the only part of the glass that is rough. If you've got a champagne glass and it's got bubbles coming from everywhere around the inside of the glass, I hate to tell you this but the glass is dirty. Don't tell your host, it won't make you popular. So in a clean champagne glass, there is a rough bit at the bottom. And champagne has dissolved gas in it, carbon dioxide at really high pressure, six or seven atmospheres, which is one of the reasons that champagne bottles are so big and so thick. And that gas would like to come out of solution but it needs a place to start. So that little roughness at the bottom of the pointy bit, those little sort of grooves in the glass, those are really good places for a new bubble. So that's why bubbles rise just from the center of the glass and they rise up in a thin column. It's because that's the place you can make bubbles.
So then you've got to worry about what happens next. And you'll see the bubbles get a little bigger as they rise because more and more gas is joining them. And as the bubbles go, they don't just move through the fluid, they actually drag liquid with it. So that thin column of bubbles sets up a bubble engine so fluid, the champagne, is being dragged up the middle and then the bubbles stay at the top but the wine has to come back down the outside. So you get this bubble engine going and that has two important consequences. The first thing is that it's always bringing new champagne to the top and that means flavors can get out of the champagne and into the air above it. And the reason that matters is because quite often when we think we are tasting things, what we are actually doing is smelling things. So when you lift a glass of champagne to your nose, just as much as what's in the wine, what matters is in the air just above it because that's the bit that goes right up your nose just as you take a sip. So if you got a bubble engine that is going round and round, it's bringing lots of new champagne to the top, so lots of flavor molecules can get released into that little bit of space. The other thing that happens is that when the bubbles come to the top and burst, they actually do the job for you. They spit little particles up your nose and so even more flavor gets delivered upwards. So this little bubble engine is really important for the flavor of the champagne.
Now, different glasses drive that bubble engine in different ways. So if you've got a nice, tall champagne flute, the sort of classic thing you get at parties, the bubble engine is going really fast, comparatively speaking. The problem is that it's spitting all this flavor into the air but your tall glass if you fill it most of the way up, all the flavor molecules just basically escape out of the glass and disappears. So you've wasted them, which is a bit of a shame.
The other sort of champagne glass you used to see is a coupe, which is a sort of very flat wide one like that. So, in this case, you've got a very shallow depth of champagne, so your bubble engine's going really slowly. So that's really good for allowing lots of complex molecules to stick to the bubbles, so the flavor molecules that the bubbles are delivering to the surface, they got lots of complexity so it's bringing out all the wonderful things that are in your wine. The problem is that, it's the same thing, when your flavor is released into the headspace just above the wine, it basically just blows away.
So it turns out that the perfect glass to drink champagne out of, if you are really a wine snob is to pick something that's about the shape of a brandy glass, which is the hard bit. Because what happens then is you get this slow bubble engine that delivers lots and lots of complexity into the air, but then it's trapped in all the space you've got up here. So when you lift the glass to your nose, that's when you get the full benefits of the flavor.