Making Antibubbles in Beer from Belgium

An anonymous reader writes "About.com reports on "Antibubbles in beer from Belgium". Scientists in Belgium have studied the movement of antibubbles (the exact opposite of regular bubbles) in Flemish beer. They found that the beer was very similar, but not the same as, dishwater. You can also learn how to make antibubbles in your kitchen from soapy water."

Comments

Water-air-water

[manganese4]

Just as a bubble is a spherical liquid membrane separating two gases (One gas being inside the spherical membrane), another definition for anti-bubble is a hollow, spherical extent of gas separting two liquids (One liquid being inside the spherical extent of gas).

Re:Raindrops

[Anonymous Coward]

The exact opposite of a bubble within a liquid, yes. But a bubble is actually a gas, trapped within a thin membrane of liquid, in gas. So the exact opposite is like they said, a liquid, trapped within a thin membrane of gas, in liquid.

Re:antibubbles and decomposition

[hurtstotouchfire]

I'd expect that in a pure liquid (They initially felt that it would be impossible to form antibubbles - it is impossible to form antibubbles (or bubbles) using pure water, alcohol or oil - a surfactant is needed.) any potential antibubbles would indeed decompose into regular bubbles. (see previous comment)

From what I can gather, the difference is the way air reacts in a liquid containing surfactants: Definition: a linear molecule with a hydrophilic (attracted to water) head and a hydrophobic (repelled by water) end. Surfactants tend to clump together when in solution - forming a surface between the fluid and air with the hydrophobic tails in the air and the hydrophilic heads in the fluid.
It actually sounds very similar to the formation of a bubble, but in this case, before the surface tension forces it into the shape of a filled sphere, the two ends of the shape are attracted to each other and attatch, trapping a globule of water. I can definitly see hydrophobic/hydrophilic forces being stronger, or at least quicker than brute surface tension. Instead of it just being a matter of the two substances (the air and water) trying to group their molecules together, there's the added draw of satisfying the hydrophobic/hydrophilic ends of the molecule by butting them up against air and water respectively.

Misnomer

[Angostura]

"Scientists in Belgium have studied the movement of antibubbles (the exact opposite of regular bubbles)"

I always get a bit annoyed when I see this type of thing. Calling them 'antibubbles' makes them sound exciting, saying they are 'the exact opposite of bubbles' makes them sound intriguing.

The exact opposite of a bubble would be an airborn droplet.

These are 'hollow bubbles' if anything

Re:Misnomer

[TeknoHog]

The problem here is that 'bubble' means two different things. A 'soap bubble' usually means a spherical layer of liquid, hanging in air, with air inside it. They have two liquid-gas surfaces. Another kind of bubble is simply a blob of gas inside a liquid; it has only one surface.

The article refers to the first kind of bubble. That way their definition of antibubble works perfectly, reversing the liquid and the gas in a (soap) bubble.

Re:Misnomer

[TeknoHog]

I'd like to add that the foamy head on the beer is made of bubbles(1) that have come as bubbles(2) from the beer below. The formation of antibubbles, as explained in the article, is again the exact opposite: you need to shoot airborne blobs of liquid (one surface) into the liquid, where it gets another piece of surface, forming an antibubble(2) of two surfaces.

Link to real article

[gnalle]

Here is a link to an article . I looks like they produce a cell membrane with air in the middle.
This membrane is stable because the hydrophobic chains of the surfactant molecules are slightly electronegative.

Re:antibubbles and decomposition

[Da w00t]

The most common place I've seen "antibubbles" (a globe of liquid floating ontop of other liquid, separated by air) has been in puddles of rain water when it's raining, and sometimes inside my 2lt bottle of coke. These "antibubbles" are really just small balls of liquid, that float and roll around ontop of another liquid, until surface tension gives way.

drink less, RTFA more

[Matchstick]

An antibubble is not a bubble that floats downwards. It's a bubble whose membrane is made of air instead of fluid.

See them at Antibubble.org

[FreeLinux]

I didn't find a video but, this site clearly explains antibubbles and includes several good pictures of them.

Re:what does

[TeknoHog]

This.

"Fluid" Troll

[CrazyWingman]

Dammit people, get your nomenclature right. Both air and water are fluids! Air is a gas (well several, but...), and water is a liquid (at room temperature, when it's called "water"...), but both of these are fluids. So, the whole "bubble of fluid inside of air, inside of fluid" doesn't really make sense.

Re:Experiments == the Scientific Method

[amasci]

Note that it's VERY easy to blow antibubbles. The main trick is to set up a clean liquid surface with a bit of detergent in the water.

Some antibubble references:

C.L. Stong, "Curious Bubbles in Which a Gas Encloses a Liquid Instead of the Other Way Around",
Scientific American Magazine, THE AMATEUR SCIENTIST, April 1974

Project websites:

J. Thomas page
http://www.antibubble.org/

Science Hobbyist Page
http://amasci.com/amateur/antibub/antibub1.html

T. Fritz page (more advanced tricks)
http://hot-streamer.com/antibubbles/

easy anti-bubble observation

[Mr. Dop]

The easy way to observe anti-bubbles is to view freshly pored pint of Guinness. You will notice that the head seems to 'sink' or dissolve from the bottom of the rim of the glass down into the glass. This is also known as the 'chocolate milk' affect due to its resemblance to this sweater drink.

No need to go down to your local pub, you can get this fresh taste by getting a can of Guinness from you local super market. It is charged with nitrogen when you open the can. The process for the 'nitrogen cakes' in the can is described in U.S. patent no. 4,832,968 .