Researchers have found that studying the cloudy emulsions produced by anise-flavoured liquors such as Ouzo might help in designing improved drugs, cosmetics.
They said their findings might lead to the design of better commercial emulsions used in making pharmaceuticals, food products, cosmetics and other materials.
Although Ouzo, Pastis, Pernod, and other popular anise-flavoured alcoholic beverages are transparent when bottled but they form milky-white emulsions when diluted with water prior to drinking, a phenomenon commonly known as the 'Ouzo effect.'
These emulsions take place spontaneously and are stable for weeks and even months, a feature that is attractive to industry. However, researchers are unclear how these mixtures form and stabilize.
In the study, Erik van der Linden and colleagues measured the stability of various emulsions prepared from commercial Pernod and compared the results to theoretical predictions of their formation.
They found that their experimental observations were often opposite the predicted behaviour of the emulsions in the presence of various concentrations of oil, water, and alcohol components.
"More knowledge of the parameters that determine the stability of these emulsions, besides interfacial tension, solubility, and density difference, might lead to better control of the emulsification process," the study stated.
Their study will be published in the Feb. 19 issue of ACS' Langmuir, a bi-weekly publication.