It's mostly about texture
Nearly every claim or standard in the cocktail making world is just one quick test away from being checked. Is that true? Is that right?
And that's what we are going to do with "shake all cocktails that contain citrus" rule.
Let's take a simple shaken cocktail, the Daiquiri, and make it two ways:
Then taste them side by side.
Let's go!
Look at all those happy bubbles on top. Not only does this given the drink a nice texture, but it also helps to release the aroma of the drink.
No happy bubbles here.
The drink is cloudy, more opaque. Again, the agitation from the shaking allowed tiny air bubbles to be captured in the pulp and pectin of the citrus.
Here the drink is more clear, more transparent. Theres some condensation on the glass adding more opacity than the drink really has.
Tasting side by side to my palate, the texture of the shaken drink was clear but subtle.
While tasting, there was something happening about 1 second into the sip of the shaken drink that seemed to be a high soft note in the middle of the mouth. Almost like a small crescendo. It's hard to explain.
The stirred drink was more flat, un-dynamic over the time the flavors came across the mouth.
These cocktails have citrus, and yet, are not shaken. Each contains no more than 1/2 oz of citrus.
Sip consciously, play with your senses