On the Velocity of Expanding Spherical Gas Bubbles Rising in Line in Supersaturated Hydroalcoholic Solutions: Application to Bubble Trains in Carbonated Beverages

Abstract

We report in this paper measurements of the rising velocity of champagne bubbles, investigated by using a camera and a stroboscopic light. It is shown that the velocity of bubbles during ascent is intermediate between that of a rigid sphere and that of a fluid sphere free from surface-active compounds. We show that our experimental results are compatible with a model of surfactant diffusive flux toward a moving sphere, suited to the case of rising and expanding gas bubbles. The critical surface concentration of contaminants needed to completely rigidify the bubble interface may not be reached in real conditions, i.e., in a flute. The rising velocity of champagne bubbles is then compared with the velocity of bubbles in beer. Contrary to champagne bubbles, beer bubbles are found to behave hydrodynamically as rigid spheres.

Effervescence in a glass of champagne: A bubble story

“…It was found that beer bubbles showed a behaviour, very close to that of rigid spheres [5][6][7], thus confirming a previous study (10). This is not a surprising result, since beer contains much higher amounts of surface-active macromolecules (of order of several hundreds mg/L) likely to be adsorbed at a bubble interface than champagne.…”

“…The gas pocket entrapped into the particle and which starts-up the bubble production process clearly appears. Such particles are responsible for the clockwork and repetitive production of bubbles that rise in-line into the form of elegant bubble trains [5][6][7]. This cycle of bubble production at a given nucleation site is characterised by its "bubbling" frequency.…”

“…It was nevertheless found that the added-mass effect of a bubble approaching the free surface never exceeds 2-3 % of its buoyancy [5][6][7]. As a result, it will be neglected in the following.…”

Unexpected behaviour of microbubbles immediately at the aerator exit

“…For example, in a diagram arranged as similar to Fig. 1(b), LigerBelair et al [8] presented measurement results obtained with the small bubbles in champagne. The data are rather scattered; nevertheless they may be described as occupying a band of velocities 0.6 to 0.8-times slower than the solitary solid sphere predictions.…”

Stabile Gasblasen – fang sie, wenn Du kannst!

“…B. bei der Freisetzung von CO 2 in Bier, Sekt und Champagner. [2] Lebendiges Sprudeln ist ein erster Qualitätstest für ein frisch gefülltes Glas.…”