Why pastis (ouzo & absinthe) turns cloudy in water
Kiss me, I’m French! Not really, but I love pastis, an anise-flavored liqueur and apéritif from France that contains 40–45% alcohol by volume. The first time I drank pastis was, as it should be, on a trip through France as a teen. Aside from wine & beer, it was my first alcohol drink.
Pastis is commonly served diluted with water, and when diluted the solution immediately turns cloudy. Finally, after years of lazy curiosity, I took the trouble to find out why…
The pastis beverages will become cloudy when diluted because they are aniseed-based. These beverages contain oils called terpenes, which are soluble in an aqueous solution that contains 30% ethanol or more by volume. When the solution is diluted to below 30% ethanol, the terpenes become insoluble; this causes a cloudy precipitate to form in the solution. The same chemistry causes absinthe to go cloudy when diluted.
Pastis is one of France’s most popular drinks, with annual consumption averaging more than 2 liters per person.
