The acceleration phase must be short and quite soon a bubble of constant gas content must reach a constant speed because of friction compensating the force pushing the bubble upward. But I don’t know within which distance traveled such a constant speed is reached. In any case, as observed above, there is the other issue of the bubbles becoming bigger along the way and therefore accelerating because of that.
How do you know that the people debating here are amateurs?
Also, I think that everybody debating her arguments here was trying to understand better the mechanism behind her claim, and with the input from several people we are slowly succeeding.
That internet allows that is indeed wonderful!
External pressure on the bubbles decreases as they rise, causing them to expand and accelerate. A phenomenon well known to divers. You can see it in slow motion videos. Here’s one, not the best but you can see some individual bubbles increase in size as they rise. It’s most noticeable as they approach the surface.
I didn´t read all postings carefully, but if I´m not mistaken a certain point is missing here:
Champagne/sparkling glasses always have a “pin point” at the bottom where the bubbles start to origine - wine glasses usually don´t have any - and therefore Champagne drunk out of wine (or brandy or whatever) glasses don´t show (almost) any bubbles - at least far less
Decent number of posts on this board about folks scratching the base of a Zalto or GGG to create the same effect.
Some champagne flutes have a rough patch at the bottom which provides nucleation sites for bubble formation, some don’t. You’ll typically see a stream of bubbles originating from the bottom in both types, maybe less in the smooth bottomed versions, because dust particles also act as nucleation sites. And you’ll see some bubbles arising from the sides of the glass as well in both flutes and regular stems because of either microscopic scratches or dust particles.
Preference for a robust stream of bubbles or more CO2 left in the wine seems to vary from person to person.
I almost never use flutes primarily because I simply hate washing them. If I am drinking bubbly, I usually reach for a Zalto white wine glass or a Zalto champagne glass (if I am feeling fancy)
I think the Reidel Sauvignon Blanc stems work well, but ‘underfilled’ flutes when we are out at parties is fine, too.
This talk about which stem begs a question: what stemware was Champagne developed with?
Given the differences stemware can make, if we do go for “bowl shaped” stems, aren’t we generating an inauthentic experience? (Even in Sauvignon Blac stems, some Champagnes can be pretty overbearing on the nose.) Perhaps we weren’t meant to be doing the nerdy tasting things we do in this manner? ![[wink.gif]](/uploads/db3686/original/2X/0/04707e6a7bbb03e0153e349d8a9270d30e1e9525.gif "wink"){kind=small}
Jean François de Troy’s 1735 painting Le Déjeuner d’Huîtres is the first known depiction of drinking Chapmagne.
Here it is in higher resolution.
https://www.virtual-wine-museum.org/wine-and-painting
Should we be interpreting Champagne through stems like those?
Even in the last 50 years, do we know what the paradigm was/is that is used by producers? Does it vary by producer?
Maybe it is time to take it to the next level and start saying, “Well, we got out the Reidel Dom Perignon stems and enjoyed the 2008 Dom, and then switched to the Schott Cristal stems for that taste…”
Historically, it was the flute that was the original high end stem. So, if we get all fancy with the new ‘tulip’ style, are we just ‘spoofilating’ Champagne?
Maybe I will start calling flute “original period stemware” (like in classical music) and admit I am ‘modifying/perverting’ the Champagne experience with my other stems.
Looks like I stirred a nest of budding scientists with the post. Not unexpected in this forum. It is good and healthy to ponder information and to raise questions. What I know is that Dr. Helen Czerski is far more knowledgeable than I am and has far more resources than I do to study the subject. She certainly has more interest in doing so as well although Champagne bubbles are not a focus of her work. They are a more light-hearted way of looking at some of here work. My best guess is that Dr. Czerski did far more rigorous experimentation than most of us are capable or interested in doing. Based on some of the comments, it clearly would have been beneficial I had provided a CV of the presenter. Without access to the academic study behind the presentation, I for one will have to settle for the results.
For the interested:
Here is a link to Dr. Czerski’s website. You will find quite a few more articles and interesting presentations there and most do not deal with bubbles in Champagne glasses. https://www.helenczerski.net/
I’m partial to Kate Moss’ left breast myself. https://www.thedrinksbusiness.com/2014/08/champagne-coupe-moulded-from-kate-mosss-breast-launched/
I actuality use Chardonnay stems most of the time. We have flutes that might get a once a year use but only for young plonk.
That’s a cool video. You can click on the speed setting and select a slower speed to watch it as well.
But, while it’s true that the pressure decreases as the bubble rise, it’s a very small change. You have to go over 30 feet in water to add 1 atmosphere of pressure. So a few centimeters isn’t adding much at all to the ambient 1 atm pressure of the air above. I think it’s just the accretion of additional CO2 from the liquid as the bubbles rise that causes the expansion (which is what the author said). They do appear to expand quite rapidly right when they get to the surface, I’m not sure how to explain that. My theory is that the refractive properties change as the path of what we see passes through the meniscus at the edge of the glass.
or you can just use the Zalto champagne glass (which is AWESOME)
Good point about depth and the possible lens effect from the meniscus. My speculation is that there may be just a little effect from the pressure gradient even though the glass is so shallow. The pressure effect on bubble size is more apparent near the surface.
30 ft = 1 + 1 atm, 1/2 the bubble size vs. size at the surface
60 ft = 1 + 2 atm, 1/3 the surface size but 2/3 the size at 30 ft
etc.
David, that math is fine, but when you drop down to just 4 inches (for example) you get 1 + 0.01 atm. So it’s only a 1% change in pressure from bottom of the glass to the surface.
That’s possible. But it also could be some sort of boundary effect as the compressible bubble gets within roughly a radius of the surface of the incompressible fluid/air boundary. Velocity of the fluid in the horizontal direction away from the bubble surface near the air/surface interface might allow expansion whereas in the bulk the fluid flow Relative to the bubble is largely vertical. I would have to put on a hat I haven’t worn in many years to think about that one.
You’re right, not enough depth for a meaningful pressure change.