What Makes Anise Liqueurs Go Milky?A cloudy appearance is actually a sign of quality.

From the show

Kitchen Wellness Secrets

That cloudy transformation in your glass of Ouzo or Arak isn't a flaw; it's a fascinating scientific event known as the 'Ouzo effect.' It's a visible sign of the natural anise oils within the spirit. When water is added, it lowers the alcohol percentage, forcing the water-insoluble flavor compounds to precipitate into microscopic droplets. These droplets scatter light and create the milky appearance—a spontaneous, stable emulsion with no additives required.