Recently I was flicking through a copy of The Curious Bartender: The Artistry and Alchemy of Creating the Perfect Cocktail (2013, Ryland Peters and Small) by Tristan Stephenson, a drinks industry consultant and pioneer of the molecular mixology movement.
Turning to the section on the Martini, I noted the inevitable reference to James Bond, but was also interested to read a passage quoted by Stephenson from The Hour: A Cocktail Manifesto by Bernard DeVoto published in 1948. The extract indicated that the debate about whether a Martini should be shaken or stirred had been a long-running one even before Ian Fleming began writing the James Bond novels.
In the extract, DeVoto dismisses as a superstition the claim that the Martini (in this case one made with gin) must never been shaken. The ingredients, he contends, are “stable, of stout heart,” and it does not matter whether they are shaken or stirred. The idea that shaking bruises the gin is, in DeVoto's view, “an absurdity.”
Tristan Stephenson does not disagree with this, and goes on to list the benefits to the drink that shaking brings. Shaken Martinis can be made quicker than stirred martinis. Shaking increases aeration, which helps release flavours and makes the drink feel lighter. The cloudy appearance of the shaken Martini slightly alters the drink's taste and aroma. In addition, Stephenson publishes a graph to illustrate how shaking reduces the temperature of the cocktail quicker than stirring does, and keeps the drink cold for longer with no further dilution. James Bond is not so incorrect after all.
The notions that shaking bruises the gin and that one should never shake a Martini are highly successful memes. They are widespread in popular culture (even beyond the world of cocktails), they have longevity (evidently pre-dating Bond), and have survived largely unchanged. That these ideas continue to be perpetuated is to a very large extent down to the success of the James Bond novels and films. As long as James Bond orders his Martini 'shaken, not stirred', the debate about the best way to make the drink is likely to run for a while longer yet.
Related post: Shaken or stirred: the debate continues.
For more information on James Bond's Martini, I recommend The Complete Guide to the Drinks of James Bond by David Leigh.