I'll just start with saying this: You can't bruise gin.However, you don't want to shake it so much that it's filled with little ice crystals and waters it down so much you'll feel like you're in a Speakeasy.
The shaking vs. stirring debate rages on and will almost always come down to personal preference. Stirring blends the ingredients (try it with different colored spirits and you'll see) while shaking it actually emulsifies it, changing the flavor.
We can all get along here. Just ask the bartender what you'd prefer and they should be glad to do it. They would rather make you a drink you like over just making you a drink that you'll tolerate.
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Martini: Shaking can bruise the gin
Comments
The Unsober Life
Martinis are meant to be as cold as possible.
There is no way to get a martini cold enough with stirring.
Shaking is the best way to get your martini ice cold - and anything less than ice cold is nothing more than cooler alcohol.
It's not using ENOUGH ice in your shaker that cause problems.
Too little ice is too quickly melted by the alcohol..causing too much dilution without enough transfer of "cold" to the alcohol.
Your shaker should be completely filled with ice. Add the Gin (or vodka if you must) and Vermouth (enough of this "dry" martini stupidity). Shake the hell out of it for 10 ish seconds. Pour into a pre-chilled martini glass and garnish with olives or a twist (Adding a cocktail Onion = Gibson NOT Martini).
You WANT a little dilution in your martini. Jut not too much.