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AAWE
Economics Department
New York University
19 W. 4th Street, 6FL
New York, NY 10012, U.S.A.
Tel: (212) 992-8083
Fax: (212) 995-4186
E-Mail: karl.storchmann@nyu.edu
Leave on your lab coat and safety goggles. Reims physicist Gérard Liger-Belair’s Uncorked: The Science of Champage is another techie read, this one taking a microscopically close look at a tiny, surprisingly interesting topic, the bubbles in effervescent wine. Uncorked is good fun in the Horatian sense, useful and charming, not unlike the beverage itself, I suppose. It presents its topic with patience and simplicity, benefiting greatly from its author’s easygoing tone and a generous number of instructive illustrations and photographs.
Facts are a poor substitute for wit, of course. But while not all of us can be witty, many of us can remember a few things. If you suspect you are a dud on the rug, listen up. This is a list of Liger-Belair champagne wow-formation.
Removing a champagne cork disturbs the thermodynamic stability reigning inside the bottle. Bubbles appear as the formerly dissolved carbon dioxide rushes like kids going on recess toward a new equilibrium, with the atmosphere outside the bottle.
An average bubble measures 500 micrometers across. In a flute of champagne, two million of these would form if you didn’t have the brains to drink it before something as explicable as that happened. (By the way, the champagne coupe may not have been modelled on Marie Antoinette’s breast. As Liger-Belair points out, it could have been Madame de Pompadour’s. Its own anatomical parallel aside, a champagne flute is in any case preferable. It extends the flow of rising bubbles and concentrates the flavors and aromas the bubbles transport.)
Bubbles do not form on tiny scratches in the crystal of your glass. The scratches are too small for that. Instead, the bubbles “nucleate” in cavities in the fibers of paper or cloth that will still be in your glass no matter how well you wipe it.
A photograph of something really little is called a micrograph. Uncorked presents micrographs of fibrous “bubble nurseries.” The busiest ones produce thirty bubbles per second, three times more than beer, dude.
Between birth and death champagne bubbles grow in volume by a factor of one million. They grow because they continue to take in dissolved carbon dioxide on their way up, up, up.
Organic compounds in champagne partially insert themselves into the surface of a rising bubble, stiffening it. This collection of surfactants, as the fragrant and flavorsome bits are known, would slow the ascent were the ongoing growth of the bubble not continually enlarging the clean surface. The surfactants end up at bubble bottom, acting like a rudder and keeping the path of the bubble straight.
Bursting bubbles launch aromatic, 100-micrometer jet drops into your nasal nocireceptors. That’s why you don’t need to swirl your flute. Interestingly, nocireceptors are there to sense noxious, potentially damaging stimulation. It’s not just buying champagne that’s masochistic.
Champagne crackles rather than producing steady white noise because popping bubbles set off chain reactions of more popping: avalanche behavior!
Bubble rafts, bubble caps, flower-shaped structures, violent sucking: Liger-Belair has plenty of pictures of stuff like this. If you are turned on by fractals, you will probably like these.
Surfactants tend to gather on the surface of the champagne, first around the rim. This eventually makes it difficult for bubbles to burst, which is why they tend to hang around longer if you are not drinking up.
Fat molecules (potato chips; lipstick) tug at the bubble membrane, and the bubble pops faster than it would otherwise.
Long-lived bubbles degas without bursting. Their carbon dioxide just seeps out in a silent sigh.
Finally, if you don’t drink your champagne but go on staring at it, you will see your bubbles revolving in little galaxies, vortex patterns determined by your cup’s circular rim. Of course, if you are drunk, the same thing may happen, which proves drunks sometimes make sense, I think.
Like Hervé This, Liger-Belair is into lifting the veil, revealing the face of an enthralling mystery. This is science, impulsively voyeuristic, typically human. Champagne, thankfully, has the power to preserve its mystique. For though I know now what Liger-Belair knows, like Faust, I feel I’m basically as clever as I was before. Champagne is still champagne, with plunging depths, euphoric velocities no camera will catch. We may be able to describe it, that is, but short of making a pact with the devil, I suspect we’ll never understand it. Champagne is chaos, true, irreducible complexity.
Peter Musolf
Yokohama
AAWE
Economics Department
New York University
19 W. 4th Street, 6FL
New York, NY 10012, U.S.A.
Tel: (212) 992-8083
Fax: (212) 995-4186
E-Mail: karl.storchmann@nyu.edu