[Greg]

Greg asked the Naked Scientists:
   
If you rub your finger on the oil next to your nose then stir your finger into
beer froth, why does the froth diminish, allowing you to pour more  beer into your mug?

What do you think?

[DeepestBlue]

OK hypothesis from an ignorant Architect.....the froth, or small bubbles exist because of the surface tension of the water in the beer.  When the oil is added (it may not be oil, it might be....euuuch never mind...), the surface tension of the liquid reduces and can no longer contain the pressure of the bubbles, hence the bubbles burst, and the head reduces in size.....

[Don_1]

That sounds pretty good to me DeepestBlue.

Can I just ask, Greg, why do you rub your finger around your hooter then stir your beer with it? I can think of better things to do with a pint of beer, like drink it and better things to do with a finger, like