Mystery of texture of Guinness beer: Inclination angle of a pint glass is key to solution

A team of researchers from Osaka University and Kirin Holdings Company, Limited demonstrated that the texture formation in a pint glass of Guinness beer is induced by flow of a bubble-free fluid film flowing down along the wall of the glass, a world first. This phenomenon is found to be analogous to roll waves commonly observed in water sliding downhill on a rainy day. Their research results were published in Scientific Reports.

source https://www.lifetechnology.com/blogs/life-technology-news-blog/mystery-of-texture-of-guinness-beer-inclination-angle-of-a-pint-glass-is-key-to-solution