We had some friends around on Friday for dinner. They brought with them a bottle of pink Cava. We didn’t finish it because they were driving home and we said, “Oh, well, we better stuff a bit of paper down to stop it going flat.” “No,” they said “Why don’t you try putting a teaspoon down the neck?” So we did.
On Saturday, the day after, we thought we’d try it with some lunch; we took the teaspoon out, poured a glass and it fizzed up like nothing on Earth! “Goodness me, how did that happen? Why didn’t the bubbles escape with all the space around the teaspoon?”
Chris - There’s no evidence, unfortunately, Gerry, that this actually works. The bottom line is - the reason there is fizz in the champagne is because the champagne was turned into wine, in other words, had alcohol in it because there was yeast, which converted sugars in the original grape juice into alcohol. When you ferment something, you grow yeast in the absence of air, the yeast produces alcohol as a by-product of survival and it also produces CO2 as the other by-product.
And if you put a cork in the bottle and pressurise the liquid, the CO2 can’t escape and therefore it dissolves in the liquid and you get a fizzy beverage. And to increase the "fizziness" of champagne what they will sometimes do is to add additional sugar after the primary fermentation and that encourages it to make even more fizz.
If you take the cork off of a bottle of champagne or a fizzy drink, what you’re now doing is exposing the gas which is dissolved in the liquid to atmospheric pressure; this means that there’s now no pressure to hold the gas in solution and it would gently and progressively come out.
And when you pour a glass of fizzy drink, you’ll see the bubbles arising from one point to a number of points on the glass and they stream upwards. That’s because there are irregularities or rough points on the surface of the glass.
But there’s no reason why a spoon in the neck of the bottle should make any difference because the bottle is open to the air and, therefore, the air above the liquid is at atmospheric pressure and, therefore, the gas will move from an area of high concentration in the liquid to the lower concentration, lower pressure in the air.
Therefore, I think this is a myth and you’d have to do a proper experiment and take several bottles of champagne and open them and put no spoon in them and simultaneously do the same thing with bottles of champagne with spoons in the neck and then have some objective measure of how much “fizziness” was in there and I think you’d find it wouldn’t make a difference. Would you agree, Dave?
Dave - Yeah, I found actually on the internet, someone has done this experiment and the spoon makes no difference at all. The important thing is putting the drink in the fridge, which makes the liquid a lot colder. And the colder liquid is the more gas it can hold. So I think it will just lose its fizz a lot slower that you’d expect when it’s in the fridge especially if it’s in a very clean bottle.
Chris - There you go, myth busted. Sorry about that, Gerry.
Gerry - That’s a disappointment.
Chris - Never mind. But drink the champagne up. I mean that’s the key thing, isn’t it?
Gerry - Oh, sure, we will next time. Oh, thanks very much for that!
Gerry Myer asked the Naked Scientists: Why does a teaspoon put in the top of a half filled bottle of Cava (or champagne) keep the drink fresh, with its bubbles until the next day at least (I've tried this - it does work) What do you think? gerry myer, Sun, 29th Nov 2009
Although I've drunk a fair amount of champagne and cava in my time, I don't ever remember hearing that one. But then the belief that it would go off if not drunk was always a good enough reason to finish the bottle (and have a new bottle the next day <wistful_sigh>I was getting 1976 vintage M&C for £11/bottle at the time</wistful_sigh>). LeeE, Sun, 29th Nov 2009
We have done the experiment and it shows little difference. Let me repost the results here: