Ouzo effect

The ouzo effect (/ˈuːzoʊ/ OO-zoh), also known as the louche effect (/luːʃ/ LOOSH) and spontaneous emulsification, is the phenomenon of formation of a milky oil-in-water emulsion when water is added to ouzo and other anise-flavored liqueurs and spirits, such as pastis, rakı, arak, sambuca and absinthe. Such emulsions occur with only minimal mixing and are highly stable.