Using Science to Step Up Your Cocktails

In the midst of the cocktail revolution, there’s no shortage of online recipes for aspiring home mixologists to shake or stir at the end of the day. However, outside of (often long) lists of (often obscure) ingredients to throw together, there’s little out there to provide an understanding of why we’re combining these ingredients and what makes a good drink. With that in mind, let’s dive into the ideas about why some drinks work, and explore how you can optimize and improve the taste of your beverages. Here’s my take on some tweaks that even the least culinarily-inclined among us could use to create the most delicious version of whatever you’re sipping. In other words, I’m not hoping to change what you drink, just to help make whatever you drink be the best version of itself.

As a template throughout these tips, I’ll use one of my favorite standbys, a rye manhattan. And though the base recipe is simple and listed below, I’ll explain how to make sure you mix those ingredients together in the best way possible.

Rye manhattan:

2 oz Rye Whiskey (Rittenhouse is great)

1 oz Sweet Vermouth (Dolin is my go-to)

2 dashes Angostura bitters

Pinch of salt

Orange peel

How to bring the most out these ingredients:

1. Refrigerate your vermouth

I’m opening with this because it’s the least well-known, yet widely distributed, fact that leads to sad tasting manhattans and other vermouth-based cocktails. Vermouth is essentially wine with spirit added to it, and like wine, its flavor changes when it is exposed to oxygen. Wine chemistry is extremely complex, but essentially, a little oxygen is okay, but over time, significant exposure to oxygen can completely ruin the bottle.

A little bit of oxygen is necessary to bring out the flavor of wine. Oxygen interacts with polyphenols (tannin, in wine speak) to soften the astringent taste of these compounds. This is why you must pretentiously swirl your Yellow Tail Shiraz around inside your glass to “let it breathe”. But if wine is exposed to too much oxygen for too long, dormant colonies of acetobacter will rise up and convert the ethanol in the drink into acetic acid.

So, if you return to the bottle of vermouth you opened a week ago expecting booze, you’ll be disappointed to find yourself drinking vinegar – not what you were hoping for (but don’t worry, this isn’t dangerous, just disgusting). To prevent this, you can buy a wine vacuum pump, which removes oxygen from the bottle so open vermouth can be stored for longer periods of time. But if you don’t have one, the low temperature of a fridge will still be very helpful in preventing bacteria from degrading the alcohol. Acetobacter function optimally around room temperature, so keeping the liquid cold will attenuate their spoiling power.

2. Add a Pinch of Salt

As culinary folk have discovered through centuries of experimentation, a little salt helps other flavors in food pop. Why not use this phenomenon to our advantage in drink recipes?

Salt is made of sodium and chloride ions (its abbreviation is NaCl, for the chemically inclined), and our taste of “salty” comes from our tongue’s ability to sense sodium ions: our tongue senses the concentration of sodium ions and converts this information into an electric signal that our brain can understand. But these senors don’t activate until salt is present in fairly high concentrations, which means you can add a little bit of salt to any drink you make (a small pinch) to enhance the flavor before it starts to taste “salty.”

But most chefs/scientists will admit that experiment beats out theory any day of the week, so to see this in action I’d recommend bringing together some thirsty friends and trying the “triangle” test, the gold standard taste test in the beverage world. The triangle test is common in reviewing beers, in fact. In this test, one fills three cups with a beverage: two of the cups with the same beverage and the third with a different one. If the single drink is significantly different than the other two (for better or worse), one should be able to identify it as the “odd one out.”

Try this with your manhattan. Make three manhattans and add a pinch of salt to one of them as you prepare it. After pouring the drinks, invite your friends into the room and ask them to taste all three beverages. Have them write down which one they think tastes best, and if more than 1/3 of your friends (random chance) prefer the salted one, you have some evidence it has improved the drink. But, by all means, don’t stop there; please use the triangle test to develop and workshop new recipes. My friends have yet to complain about having to try multiple cocktails prepared for them. Just keep in mind that the results tend to become less reliable later in the evening after several rounds of drinks.

3. Stirring vs. Shaking

Now that the ingredients are assembled, you may be wondering whether to stir or shake them. While personal preference has many places in mixology, for this manhattan, the answer is unambiguous: stir. The reason is pretty simple: shaking introduces air into the liquid and breaks up the ice into fine crystals making the drink opaque and giving it a frothy texture. Stirring takes longer, about 30-50 seconds depending on technique, but it doesn’t introduce air, keeping your drink clear and silky.

A rule of thumb is if you have clear ingredients, you should stir to keep it clear. This is (partly) why every bartender in the world will judge you when you ask for your martini “shaken, not stirred”, and will dread rewarding your pitiful Bond impression with a sub-par drink. On the other hand, if you want to drink a cold and frothy combination of lemon juice, honey syrup, and scotch then shake it. Don’t trust me? Try it yourself. Try making two manhattans – shake one and stir the other, and then place them side by side. Besides the stirred beverage looking crystal clear and beautiful, you’ll notice that it will also just go down smoother, and you’ll never want to shake a manhattan again.

Notice the difference between a stirred manhattan (left) and a shaken manhattan (right).

4. Express the Citrus

Expressing an orange peel over a manhattan

Many recipes out there include an instruction like “serve with a lemon peel,” and in the case of our beloved manhattan (which is almost complete) it goes great with an orange peel. The single most important thing you can do with these peels is “express” them over the beverage. This is just a simple act of twisting them (or pinching them) over the top of completed beverage and running it around the rim of the glass afterwards.

Honestly, it doesn’t matter if you toss it in the drink after or throw it in the trash, it’s done its job. The flavor we’re after is in the oils that sit in the pores of the orange peel, which are the compounds responsible for an orange’s smell. These oils are volatile, meaning they partially evaporate into the air, where they can drift into our nose and cause us to think “that smells like an orange”. Without expressing the peel, those oils remain trapped in the peel and can’t give your manhattan the same fantastic finish. Do yourself a favor and watch as you squeeze the peel over the top of the liquid, you’ll see all those little pores pop and you can watch the orange oils float aimlessly across the drink.

The finished product

Finally, with all these tips in mind, you should be able to stir up a very respectable and Instagram-worthy manhattan. I like to stir mine for a very long time to cool and dilute it (it’s a strong drink to begin with), then strain it into a coupe glass (pictured) before expressing an orange peel over the top and throwing it in. But this is your drink! If you want it stronger, don’t stir as long, and if you have a affinity for grapefruits, use a peel from that instead of an orange. Either way, just make sure it’s engineered to be optimized for your taste.

Stay tuned for more advanced tips that allow more experimentation and creativity when mixing up drinks. Also, shoutouts to Dave Arnold, author of Liquid Intelligence and proprietor of Existing Conditions in NYC, for offering clarity to me around these concepts.

Bonus: Substitute Blue Curaçao 

Some people are pretentious about blue drinks. I don’t care one way or the other, but nevertheless, my family makes “blue whales” every 4^th of July, which, as the name implies, are blue. But here’s a secret: when or if you buy blue Curaçao, the manufacturer is selling you triple sec with blue food dye. That’s fine if you want blue color for your drink, but the triple sec they use is almost always awful. Do yourself a favor and just pick up some triple sec that doesn’t taste like gasoline mixed with hi-c. Cointreau is the gold standard (I also mean that literally – it sets the price bar high as well), but even mid-range bottles will be an improvement. Since you probably still want that blue color, add food coloring yourself, and you’ll now have a delicious blue Curaçao.