Sinking bubbles in stout beers

Sinking Bubbles in Stout Beers

9 A surprising phenomenon witnessed by many is the sinking bubbles seen in a settling pint of 10 stout beer. Bubbles are less dense than the surrounding fluid so how does this happen? Previous 11 work has shown that the explanation lies in a circulation of fluid promoted by the tilted sides of the 12 glass. However, this work has relied heavily on computational fluid dynamics (CFD) simulations....

Mathematical Modelling of Bubble Nucleation in Stout Beers and Experimental Verification

Bubble nucleation is a phenomenon observed in many different physical situations from decompression sickness (DCS) to champagne research. It is of vital importance to the formation of a creamy head that is distinctive to stout beers. As stouts contain a lower quantity of dissolved carbon dioxide than other beers, nitrogen is also dissolved in the beer. This is necessary to produce the smaller b...

2 9 M ar 2 01 1 Bubble nucleation in stout beers

Bubble nucleation in weakly supersaturated solutions of carbon dioxide—such as champagne, sparkling wines and carbonated beers—is well understood. Bubbles grow and detach from nucleation sites: gas pockets trapped within hollow cellulose fibres. This mechanism appears not to be active in stout beers that are supersaturated solutions of nitrogen and carbon dioxide. In their canned forms these be...

Clifford Beers

A great reformer has passed on. Clifford Whittingham Beers died on July 9th, 1943, at Providence, U.S.A., but his fine enthusiastic and farseeing spirit has left behind it work which persists and grows. At a time when such ideas as his were regarded as almost too progressive, and, in some quarters indeed, as subversive and revolutionary, he, a recovered patient, demonstrated the value of indivi...

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