Their advance could shed light on why the foam on a pint of lager quickly disappears, but the froth on a pint of Guinness sticks around.

• 他们的研究结论可能可以解释，为何一大杯黑啤酒的泡沫会迅速消失，但一杯Guinness啤酒的泡沫会留著的原因。