It actually makes no difference whether your
martini is
shaken or
stirred; it's going to taste the same either way.
Note: see below for a retraction.
If you think about it, this makes
James Bond kind of an idiot -- the bartenders are rolling their eyes behind his back as soon as the camera pans away.
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Update: Apparently I'm wrong and there is a difference between a shaken or stirred martini (thanks to
Footprints for correcting me). In addition to the decanting/not decanting distinction, shaking a martini can, apparently, bruise the
gin and make it cloudy.
On the plus side, according to a Canadian study, a shaken martini may contain more
antioxidants than a stirred one. This could be why Bond doesn't have
cancer after all these years of hanging out in smoky
casinos.
However... I maintain Bond is an idiot. First off, a
real martini is always made with
gin, not
vodka (as
007 orders it). And secondly, according to some, when you shake a martini instead of stirring it's not a martini anymore; it's a drink called a "
Bradford."