A single pint of beer contains up to 2 million bubbles

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Tilting a beer glass while pouring can lower the amount of bubbles that form

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When beer is poured into a 500-millimetre glass, somewhere between 200,000 and 2 million bubbles rise to the surface to form the foamy head.

This estimate was made by Gérard Liger-Belair and Clara Cilindre at the University of Reims Champagne-Ardenne in France, who calculated the number of tiny bubbles that form before a lager goes flat.

The team first measured the amount of carbon dioxide dissolved in 250 millilitres of lager after it was all poured into a tilted glass. They …