What is the significance of James Bond’s famous phrase “shaken, not stirred”?

  • From issue 2759 of New Scientist magazine, page 65 and issue 2813 page 62 and issue 2763  page 69.

What 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? 
 Mark Langford, Stockport, Cheshire, UK
• Supposedly, when a martini is shaken, not stirred, it “bruises” the spirit. To seasoned martini drinkers this changes the taste.
Padraic O’Neile, Newcastle, New South Wales, Australia
• 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 Brooks, Bristol, UK
• 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 Calverd, Bishop’s Stortford, Hertfordshire, UK
We have since learned, however, that other chemical reactions may be taking place – Ed
• 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 McNally, Vancouver, British Columbia, Canada
• 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 Melly, New 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
• 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 Collins, Washington DC, US
• Anna Collins of Washington DC told us that the reason James Bond ordered his martinis shaken was that at the time the Bond novels were written, vodka was widely made from potatoes rather than grain, as is common today. Potato vodka is noticeably oily and shaking it with ice dissipates the oil. This was confirmed in a blind tasting by reader Peter Simmons, of London.
However, another reader in the UK, William France of Birmingham, wrote in to point out that in the book and movie Casino Royale Bond orders his martini to the recipe later known as a vesper, which contains more gin than vodka, yet he still requests that it is shaken. So why? – Ed
• Bond’s martini in Casino Royale is made to the following recipe with thanks to the 1953 novel by Ian Fleming:
“A dry martini,” [Bond] said. “One. In a deep champagne goblet.”
“Oui, monsieur.”
“Just a moment. Three measures of Gordon’s [gin], one of vodka, half a measure of Kina Lillet. Shake it very well until it’s ice-cold, then add a large thin slice of lemon peel. Got it?”
“Certainly, monsieur.” The barman seemed pleased with the idea.
We can also presume the vodka used was a potato vodka because Bond goes on to tell the barman: “Excellent… but if you can get a vodka made with grain instead of potatoes, you will find it still better.”
So we know there is a measure of potato vodka in the vesper. To check whether this still makes a difference to the martini, I and four friends repeated Peter Simmons’s blind tasting of the martinis, making one batch with potato vodka and another with grain. We had to amend the recipe slightly because the Kina Lillet in the vesper (which replaces the dry vermouth used in standard martinis) is no longer produced, the nearest modern-day product being Lillet Blanc. Lillet Blanc is less bitter than Kina Lillet (Kina referring to the bitter quinine that was in the original) so we had to add two drops of bitters to the drink so it matched the original vesper taste.
Without a doubt, the potato vodka vesper was oilier than the grain vodka version (despite containing only a single measure of gin, as opposed to three). And subsequently when shaken with ice, the oil in the potato-vodka vesper was much less pronounced. All tasters were unanimous in detecting this.
Thus, despite the modern convention of stirring martinis, it seems that Bond, a man of obvious sophistication, knew what he was talking about when always asking for his martinis to be shaken, recipe notwithstanding.
Janice Devaney, London, UK
• Anna Collins is correct, according to our blind trial. We bought two bottles of vodka, one grain, the other potato-based. First we tasted the vodkas. In the blind trial all six people in our sample said the potato vodka was oily, and the grain vodka wasn’t. Then we made two vodka martinis using the potato vodka. One was stirred with ice, the other shaken with ice. The difference was quite distinct and in a blind tasting every one of the six drinkers characterised the shaken martini as being much less oily. But the martini had to be consumed quickly. If left to settle for 5 minutes or so, the shaken martini became oily again.
Peter Simmons, London, UK
Our final advice is to go easy on the vodka martinis, whether shaken or stirred – Ed