Advanced Craft Cocktail Theory: Aroma and Flavor
To all of you who survived my first set of articles dealing with theories of craft cocktail construction, I say congratulations. Now the hard work begins. While it’s nice to have a solid understanding of the fundamentals of how and why certain craft cocktails work and others do not, there’s a lot more ground to cover in the service of better cocktails.
To this end, I will be writing an open-ended series of articles that deal with refining craft cocktails. Subjects will include aroma and flavor, texture, visual appeal, harmony, context, and inspiration by theft. I’m going to assume that you are comfortable with my original four-part series, and that you’re up for some heavier reading and homework. Are we ready? Let’s begin, shall we?
Unlike the other five senses, no one can say for sure how we smell anything. There are theories out there, each full of massive, unexplained holes. Science has identified G-protein receptors in the neurons in the nose that work together to build a scent out of basic component parts. This won Linda Buck and Richard Axel the 2004 Nobel Prize in Medicine. We know what parts of the brain process this information. We know that we can certainly smell things (and weirdly enough, we can smell everything that has a smell, and we can do it instantaneously – something that violates rules about how the body works).
There are two competing theories about how we smell things. The first of which is Shape, which posits a “lock and key” mechanism where the molecular shape of odorant molecules fit a certain shaped receptor. Once this match is made, the receptor fires off a signal to the brain that says “eugenol”, “camphor” or “vanillin”. First proposed in 1949 by R.W. Moncrieff and refined significantly by John Amoore, this theory is now widely accepted by both perfumers and scent researchers, but fails in a few crucial ways: Humans have 347 different scent receptors but can smell at least tens of thousands different aromas. Second, shape theory fails to predict aromas based on the shape of the odorant molecule. Some researchers propose what is called “weak shape”, where parts of odorant molecules fit differently shaped receptors, but this too has problems.
The other theory of how we smell things is actually older than Shape. In 1937, Malcolm Dyson gave a speech to the British Society for Chemistry and Industry that put forth the idea that scent was determined by the molecular vibration of the bonds of the odorant molecule – in effect saying that humans use electron tunneling to perform molecular spectroscopy on the odorant chemicals, which then trigger the brain to recognize “eugenol”, “camphor” or “vanillin”. This was pretty much forgotten about until Dr. Luca Turin picked up Dyson’s idea, gave it a lot of polish, and proved that it (theoretically) could work. Chandler Burr wrote “The Emperor of Scent” about Turin’s theory in 2002. The problem here is that while Dr. Turin makes a lot of claims that support his theory, and he’s certainly correct about the lack of hard data from the Shapists, no one can seem to reproduce his data.
So what does all this mean to someone out to create a craft cocktail? First off, let’s dispense with something easy: Ninety percent of what you taste is what you smell. The sense of smell is staggeringly more complex and better equipped to deal with sensory information than the sense of taste (remember…. tens of thousands of aromas, but only six flavors).
To make matters worse, cocktails are intentionally designed to be low aroma. In order to smell something, it has to evaporate. Think about a wine glass, which has a large volume and an exaggerated “bowl” shape which allows the drinker to swirl the small volume of wine up onto the glass. This lets alcohol evaporate, carrying odorant chemicals with it. The top of the glass is typically tapered, which concentrates aroma. Finally, most wines are served between 45 and 70 degrees Fahrenheit. All of these lead to more evaporation and more concentration of aromachemicals – wine glasses aim to enhance aroma.
Now think about a typical cocktail. The glass is much smaller, it is not tapered at the top, and it is filled very full of very cold liquor. Not a lot of evaporation here! Even worse are those cocktails that contain egg whites or dairy, both of which decrease the ability of odorants to evaporate. In fact, I don’t think you could design a worse way to actually smell a cocktail than how they are made everywhere today.
There are obviously easier and more difficult ways to create aromatic craft cocktails. Forbidding dairy or eggs in drinks doesn’t make a lot of sense, and neither does serving cocktails at room temperature. I would recommend moving away from coupe-style glassware toward those with more of a bowl shape, making smaller cocktails that don’t quite fill the glass, and making cocktails that are higher proof as three easy solutions.
Another area to explore is selecting ingredients that have a lot of aroma (or lots of ingredients), and specifically those with aromachemicals of a low molecular weight (things smell like fruit and flowers), which evaporate easily, and before heavier weight scents such as wood. A good test of this theory is to take ¼ ounce of Rothman and Winter’s Crème de Violette and dilute it with ¼ ounce of water in a standard 5 ounce wine glass. In a second glass, put ½ ounce of Oloroso sherry. Smell the glasses, swirl and smell them again, then let them sit some place overnight so that the liquid evaporates. The next day, smell both glasses again. The glass with the Violette will not smell that strongly, but the glass that formerly held the sherry will have a strong base note of old wood, furniture polish and walnut shells.
Cocktail bitters are another great way to enhance the aroma of a cocktail. These are uniformly meant to provide bitterness and aromatic punch in a small volume of liquid, especially the darker-colored Angostura and Fee Brother’s Whiskey Barrel Aged bitters.
It is also worthwhile to use rinses, atomizers and garnishes to provide aromatic punch. One of the joys of a mint julep is cutting the straw short and getting the nose deeply into the mint garnish. Expression of citrus oils over the top of a drink provides a high level of aromatics as well. Highly aromatic rinsing/atomizing agents go a long way toward enhancing the aroma of a drink. Finally, garnishes should not be overlooked, as fresh fruit and herbage provide a visual reminder of the aromas already present.
As a homework assignment, I’d like you to make two Daiquiris. One a standard version with 2 ounces of dry white rum (like Flor de Caña), 1 ounce of lime juice, and ½ ounce of simple syrup. The second is another Daiquiri, but this time, 2 ounces of Flor de Caña, ½ ounce simple syrup, and ¼ ounce of Lactart, with a lime peel expressed over the top of the drink. The question is which drink is more aromatic and flavorful, and what else could you do to increase the aroma?
This is the first in a series of advanced cocktail construction tutorials. Want the introductory series? Start with acidity.