Cocktail Queries: Why Do We Shake or Stir Certain Drinks?

Cocktail Queries is a Paste series that examines and answers basic, common questions that drinkers may have about mixed drinks, cocktails and spirits. Check out every entry in the series to date.

This is truly a lesson in bartending 101, but one that isn’t obvious to the average home consumer unless they understand a bit of the science of dilution: Why are some cocktails classically stirred, while others are violently shaken? What’s the difference between these two methods of preparation, and why do shaking and stirring each suit certain types of drinks? At the end of the day, why does it matter how you chill your cocktail? Let’s find out.

What is the aim of chilling and diluting a cocktail in the first place? Well, there are several reasons. First, the act of mixing over ice gives cocktail ingredients a chance to more harmoniously blend together, creating a new flavor profile that isn’t achieved by simply mixing two liquors in a glass. Dilution is an important, often misunderstood aspect of liquor/cocktail consumption, as we addressed in this piece on diluting whiskey. Many spirit-heavy cocktail recipes, such as a classic martini, might seem unnecessarily harsh without at least some level of dilution. Chilling the drink, meanwhile, accomplishes the same thing, making flavors more approachable and refreshing. The end goal is often to create a drink that is lively and flavorful, but also easy to consume.

Not all methods of adding ice to a drink are created equal, however. Combining ingredients with ice and then stirring them with a bar spoon creates a different sort of drink entirely from slapping a top on the glass and giving it a long shake. Although both achieve dilution and chilling, here’s how the methods significantly differ.

Stirring Cocktails

Unsurprisingly, stirring a cocktail is a more gentle motion and process than shaking it all over the place. Stirred drinks traditionally are spirit forward and contain fewer ingredients—often only liquors and liqueurs. A classic martini, for example, is nothing more than gin and vermouth, making it perhaps the epitome of the classically stirred drink—something that sometimes surprises people when they’re familiar with James Bond’s famous request to have the drink “shaken, not stirred.” That one line, in fact, has resulted in decades of confusion over what is acknowledged as the standard way to make a martini, but to put the debate to rest: It’s stirred, not shaken. The latter just sounded like a cool line.

Why stir a martini, though? Well, for one, the gentler act of stirring results in less chipped or broken ice, which means a crystal clear cocktail—which is considered aesthetically desirable in a martini. Stirring also tends to lend a fuller, more smooth mouthfeel to drinks, which is considered desirable in many cocktails that are spirit forward. In general, a stirred martini would be a bit more silky smooth, clearer, and more uniform in texture than a shaken one. A stirred martini will also be somewhat less diluted than a shaken one would be.

The classic martini is crystal clear.

You can apply this principle on a wider level to establish a general rule of thumb: If a cocktail is meant to be crystal clear in the glass, it should be stirred. If it’s meant to look cloudy, then it should be shaken. This means that classics such as the manhattan (whiskey, vermouth, bitters) or the negroni (gin, Campari, vermouth) end up being stirred drinks, where you can admire their brilliant clarity. Drinks that incorporate significant amounts of citrus juice, egg white, cream/dairy or sour mix, on the other hand, are naturally going to be less clear, which means there’s effectively no reason not to shake them.

There’s some mythology to the shaken vs. stirred debate, which in some places you’ll see as claims that gin and whiskey cocktails should be stirred because shaking will “bruise” the spirit, hurting its flavors in some way, but this is primarily pseudoscientific at best. Instead, let the other ingredients involved determine whether you’re stirring or shaking.

Shaking Cocktails

Shaking a drink is a far more vigorous, violent process, which means several things for the final product. First of all, it’s going to chill a drink quicker, because the process of dilution will be more efficient and intense. That also means the drink will become more diluted in the same period of shaking, vs. stirring.

Shaking will also result in textural changes to the drink. The violent motion will break the ice apart more frequently, resulting in tiny ice chips in the finished drink. Many bars will choose to double strain a shaken drink for this reason, to remove these tiny chips of ice. Other drinkers may actually appreciate this particular texture, and choose not to double strain. Regardless, the more important effect on texture of a shaken drink is aeration, as the act of shaking whips more air into the liquid, which you are avoiding with a gentle stirring motion. For this reason, a shaken drink will have tiny bubbles of air whipped into it, resulting in a more foamy, frothy, lighter texture. If you actually shook a martini, for instance, to bring Bond back into the equation for a moment, the resulting drink would be frothier and lighter than the more smooth, silky stirred martini, and probably taste a bit more diluted as well.

Shaking cocktails is the go-to process for mixing drinks that include large amounts of fruit juice, dairy/cream liqueurs, simple syrup, eggs or sour mix, primarily because the act of shaking does a more complete and efficient job of combining these ingredients (which have different textures/densities than liquor) with a liquor base, making the drink less likely to separate after chilling. This also makes the flavors of a drink coalesce in a more harmonious way than stirring would, particularly in drinks with many ingredients. These are all reasons why, for example, the vast majority of tiki drinks are shaken rather than stirred.

Almost always shaken, rather than stirred.

Classically shaken drinks include the daiquiri, which benefits from the shaking action to combine large amounts of lime juice and simple syrup with the differing density of rum. The frothy, aerated texture also makes a classic daiquiri more drinkable and spritzy than the drink would be if it was stirred. Using this logic, you also shake drinks that include such ingredients as pineapple juice (jungle bird, etc), cranberry juice (cosmopolitans) or egg white (Ramos gin fizz).

That last drink, the fizz, raises an important exception that is pretty obvious when you think about it—if there’s a carbonated or fizzy element to the drink, you shake the rest of the ingredients before adding it. A cocktail with soda water, tonic water or champagne, for instance, should not be shaken after that ingredient has been added, or all the carbonation will be released, effectively making your drink go flat before you’ve even tasted it. Instead, add these ingredients at the very end of the cocktail building process, either as a float, or very gently stirred into the drink.

This little rule of thumb will provide you with the best possible home cocktails, whether that’s a silky smooth martini or a refreshing summer daiquiri.

Jim Vorel is a Paste staff writer and resident liquor geek. You can follow him on Twitter for more drink writing.