It’s the holiday season, and for many that’s reason enough to indulge (responsibly) in a mixed drink at a holiday gathering. But as you’re convivially tossing one back, do you ever wonder why a drink looks and tastes the way that it does? Harvard University physicist David A. Weitz and grad student Naveen Sinha offer a unique look at the science behind mixology, including techniques for building a better cocktail.
According to Weitz and Sinha’s report in Physics World magazine, our sensation of a mixed drink can be broken down into three elements: flavor, appearance and texture. Ethanol, also known as pure alcohol, is the delivery mechanism for flavor. On the molecular level, ethanol does a great job of trapping aromatic molecules in an aqueous solution (i.e. your cocktail) in addition to extracting flavors from flowers, spices and fruits. (Think infusions: if you’ve ever tried flavoring vodkas by adding in whatever tickles your fancy, after letting it set for a few days you get a flavorful spirit.) Some bartenders are even utilizing lab equipment such as rotary evaporators, which can distill a liquid’s aroma molecules to attain more potent flavors.
It also turns out that when it comes to creating the look of a drink, the method of mixing can make all the difference. For example, a Manhattan—composed of whiskey, sweet vermouth and bitters—is clear when stirred but cloudy when shaken. This happens because shaking introduces air bubbles, which scatter light and produce an opaque drink. Shaking also impacts texture and produces more viscous drinks. While 12 minutes may sound a little extreme to create a Ramos gin fizz, the air bubbles in the drink progressively divide into smaller bubbles during the mixing process, with the end result being the drink’s signature stiff layer of foam strong enough to support a metal straw. Some chefs have taken the element of texture to extremes to create drinks that have chewy or even solid consistencies. With an understanding of how cocktails work on a molecular level, it will be interesting to see what new concoctions mixologists will offer us.