Scientists have discovered that the shapes formed by water and ethanol molecules in alcoholic drinks impact their flavor profile. This explains why a glass of whisky neat tastes more alcoholic than having it on the rocks. When water and ethanol molecules cluster together at different temperatures, it affects the taste of the drink.
In a recent study conducted by Lei Jiang and his colleagues at the Chinese Academy of Sciences, the molecular makeup of alcoholic beverages like beer, rice wine, and baijiu was examined. They measured the surface tension of different alcohol types and used imaging techniques to study the clusters of water and ethanol molecules at various alcohol levels and temperatures.
Results from taste tests conducted in partnership with Chinese baijiu brand Wuliangye showed that colder and less alcoholic liquids were associated with a more refreshing flavor due to the structure of their molecule clusters becoming more compact at lower temperatures. Warmer drinks and those with a higher alcohol by volume (ABV) were perceived as more pungent and alcoholic because of their different cluster formation.
While the study provided insight into how temperature and ABV impact the taste of alcoholic beverages, Gavin Sacks from Cornell University cautioned that the relationship between molecular clusters and taste is complex. He explained that the same receptors in the mouth can be triggered by the burning sensation of alcohol as well as heat.