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Stirring stuffWhat is the significance of James Bond’s famous phrase “shaken, not stirred”? Is there really a difference in the taste of a shaken vodka martini, as opposed to a stirred one? And if there is, why? (Continued)Mark LangfordStockport, Cheshire, UK

The shaken-versus-stirred dispute has run for years in The Last Word. One of our books, How to Fossilise Your Hamster, drew on the following three answers to explain the differences. However, more information has come to light – Ed

n Supposedly, when a martini is shaken, not stirred, it “bruises” the spirit. To seasoned martini drinkers this changes the taste.Padraic O’NeileNewcastle, New South Wales, Australia

n Because a martini is to be drunk within seconds of preparation rather than minutes, there is a difference. The tiny bubbles caused by shaking mean a well-shaken martini is cloudy. Shaking will also have an effect on the drink’s texture – making it less oily than the stirred version – and hence on the taste. The long-standing assumption that the spirit is bruised by the process is nonsense; vodka does not have a vascular system.Peter BrooksBristol, UK

n Bond may have appreciated the softening and ripening effect of partial oxidation of the aldehydes in vermouth – akin to letting red wine breathe before you drink it. In a refined and homogeneous substrate such as vodka martini, a good shake can speed the process.Alan CalverdBishop’s Stortford, Hertfordshire, UK

We have since learned, however, that other chemical reactions may be taking place – Ed

n Biochemists at the University of Western Ontario in London, Canada, have suggested the change in flavour brought about by shaking is due not to the oxidation of aldehydes, but to the breakdown of hydrogen peroxide. Stirred martinis have double the amount of hydrogen peroxide of shaken ones.Peter McNallyVancouver, British Columbia, Canada

n The reason shaken martinis are cloudy is not so much down to bubbles, but because the crushed

ice in the shaker deposits tiny ice crystals into the poured drink. The drink slowly clears as the crystals melt.Frank MellyNew York City, US

This called for more research. Was it bubbles or ice causing the cloudiness in a shaken martini?

First, we needed a good recipe. This came from mixologist Eric Keitt who works the bar at Oceanaire in Washington DC: “You will need a double vodka and two or three drops of dry vermouth. Pour into a cocktail shaker with

crushed ice and shake until the hand holding the shaker is very cold, then strain into a martini glass. Add an olive or a twist of lime zest.” Eric tells us that vermouth releases the aromatics in the vodka, making for a more enjoyable drink.

We made three vodka martinis using Eric’s recipe. The first was shaken with crushed ice. It was very cloudy and took a long time to clear, but as far as we could tell the cloudiness was due to tiny bubbles from the shaking plus the condensation on the chilled glass. Any ice crystals present must have been microscopic and were not apparent to the eye.

The second was a room-temperature martini, shaken without ice. There were bubbles in the poured drink but they quickly dissipated, much faster than in the iced martini.

The third martini was made in an attempt to replicate conditions in the iced martini but without adding ice. The martini and its

shaker were wrapped in a drinks chiller until they were at the same temperature as the first martini, then shaken. When poured, this stayed cloudy for much longer than the room-temperature drink, but not as long as the iced martini.

We reached the view that ice does have some effect on the clouding process, as do cold conditions, but none of this is conclusive. Can any readers take a look through a microscope at a vodka martini shaken with ice, to rule out or confirm the presence of ice crystals? – Ed

n The reason Bond orders his martinis shaken is that the ice helps to dissipate any residual oil left over from potatoes – the base ingredient for many vodkas at the time Ian Fleming’s novels were written. With the rise of higher-quality grain vodkas, shaking is unnecessary, and for many fans of the vodka martini, shaking the drink with ice dilutes it too much. Stirring with ice chills it without reducing its strength.Anna CollinsWashington DC, US

Looks like we need to get down and dirty with potato vodka now. This one could run and run – Ed

This week’s questionscold ruShI have heard that submarines travel faster in colder water. Why?Brendan ReillyDublin, Ireland

“Stirred martinis have double the amount of hydrogen peroxide that shaken ones contain”

“Shaken martinis are cloudy because shaking deposits tiny ice crystals into the poured drink”

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