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34 | Chemistry World | December 2010 www.chemistryworld.org Shaken, not stirred Can’t we just enjoy at Christmas without worrying about the science behind them? Not if the molecular mixologists have got anything to do with it. Hayley Birch ventures to the bar

A few years back, Darcy O’Neil the University of Western Ontario. ‘Ramos gin fizz’, a cocktail with its was tending the bar at a Canadian In short But recalling his days behind the origins in 19th century New Orleans, fine dining restaurant called Mint  Science is beginning bar at Mint, he says his scientific US. Done right, it is the perfection of in London, Western Ontario. to catch up with the art approach to mixing a drink raised the shaken egg drink that was popular Sometimes, when the bar was of mixing drinks, giving more than a few eyebrows. ‘Most at the time, he says. And it’s evident quiet, he found himself chatting to birth to the field of people are surprised that a bartender just from the recipe, with its precise customers – about this and that, but ‘molecular mixology’ is knowledgeable about these things, timings (‘blend for 20 seconds... shake often about the drinks. It was the  Most research is and they find it fascinating,’ he says. for 30...’) and quantities, that nailing cocktail menu that really piqued done behind the scenes ‘Feeding them information on the this cocktail requires the maker to their interest. What’s in this one? in makeshift labs or by scientific aspects of a drink is a great adopt the methodical approach of a How do you make that foam? Why chemists in their spare way to make their experience at the skilled scientist. shaken, not stirred? They weren’t time bar more enjoyable.’ Key to achieving the drink’s foamy expecting scientific answers by  Chemistry has shed A simple example is O’Neil’s texture are albumin proteins present any means, but that’s what they light on myths about ice got, because it was to his first love – and shaking drinks, and chemistry – that O’Neil returned to inspired new ingredients satisfy their curiosity. and techniques Schooled as a chemist at the University of Western Ontario (also in London), O’Neil had since held several jobs in the petrochemical and pharmaceutical industries before taking a break from science to learn the ‘art of drink’, now the title of his cocktail blog, one of the most popular on the web. But if making cocktails is, as his blog proclaims, an art, it’s one that’s largely dependent on science. Though you will rarely see a mentioned in a peer-reviewed paper, the scientific principles that go into creating the favourite tipple of ’s are more sophisticated than some of his imaginary gadgets. And now, riding on the coattails of culinary institutes involved in ‘molecular gastronomy’, experimentalists in the cocktail business are employing scientific principles to take the drinks industry into entirely new realms. Mixologist Darcy O’Neil Service with science applies his chemistry O’Neil has since returned part-time skills to create new drinks

to continue his career as a chemist at and refine old recipes O’NEIL DARCY www.chemistryworld.org Chemistry World | December 2010 | 35 Cocktail chemistry in egg whites. The shaking action 007’s vodka martini stretches and unfolds the protein molecules, encouraging them to 15ml form a network that traps air and 60ml potato vodka results in the froth characteristic of A of lemon peel, to garnish the traditional gin fizz. Nowadays, Ice cubes though, it’s rare to find a bar that serves drinks containing raw eggs Method: Shake the vodka and because of the risk of Salmonella vermouth together 20 times in a DANJAQ/EON/UA / THE KOBAL COLLECTION COLLECTION KOBAL THE / DANJAQ/EON/UA contamination. Many bars miss with several ice out the eggs altogether, but as cubes. Strain into a O’Neil notes, substituting them for and garnish with the lemon. powdered egg white (guaranteed to be Salmonella-free) gets around the problem. to around 20 shakes. Any more and you’re just wasting your energy. Shaken, not stirred Webster is impressed by such Coming from a scientific innovation. ‘I think some bartenders perspective then, it’s easy to will appreciate that,’ he says. He’d understand the importance of like to employ similar levels of a good shake to the texture of a scientific rigour to test what happens cocktail. But what about the taste? to the taste if you shake a vodka Why, for example, would film spy martini versus stirring it. He’s also James Bond have wanted to order throwing gin into the mix – shaking a drink containing no trace of egg a gin cocktail incorporates air, which white – the vodka martini – shaken is said to ‘bruise’ the gin, supposedly and not, as he was so famous for causing flavour chemicals in the specifying, stirred? spirit to oxidise and creating a One theory, according to Shawn sharper taste. But it’s probably just Webster, who has recently been being the best ice for cocktails,’ James Bond famously another spurious theory. ‘A scientific involved in researching cocktails O’Neil explains. ‘And this research asked for his martinis test really has to be done – like with as part of an outreach project at by Eben basically said, “No, ice is shaken, not stirred. But the 20 shakes – to see if there is a the University of Aberdeen, UK, ice and in a cocktail you can shake it why? It’s all in the oils difference in taste between one that relies on the assumption that back to a certain point and that’s as cold contains vodka and one that contains in the 1950s, Bond would have been as it’s going to get”. So it actually both vodka and gin,’ says Webster. drinking vodka made from potatoes. helps bartenders understand that, As he explains, oils present in the you know, you shake a cocktail 20 Guerrilla science potatoes – but not in the grains that times and then it’s cold.’ Klemm’s Like most of the research that’s been are more commonly used to make work showed that under normal carried out on cocktails, however, vodka today – are dispersed by conditions, most cocktails will not Klemm’s cocktail shaking work shaking. ‘The shaking will get rid get any colder than –7ºC, equating wasn’t published in a scientific of the oily taste which is associated journal. As O’Neil says, there’s never with the vodka. However, if you just going to be any money for a major mix it then the oily taste will still be Ramos gin fizz research project in cocktail science. prominent in the drink.’ Any research that is going on is being Another reason that a vodka 60ml gin (Plymouth) done in personal time and with 1 martini, or any cocktail for that ⁄2 egg white whatever scientific apparatus the matter, is shaken is to get the ice in 15ml simple syrup* experimenters can lay their hands contact with the liquid, making sure 15ml lemon juice on. ‘I’m lucky, I work at a university it’s ice-cold for service. Although in 15ml lime juice part-time so I have access to some the case of the martini, it’s perhaps 30ml cream of this equipment,’ he says. ‘Many more relevant – an unshaken 3 drops orange flower water of the researchers are curious martini can taste like lighter fluid, 30-60ml soda water about these oddball things I guess, according to Webster. Shake it for but actually embarking on a major too long, however, and the ice melts, *Simple syrup is 2 parts sugar research project? There’s obviously diluting the drink. dissolved in 1 part water not a lot of funding.’ In the past, ice companies have O’Neil has, himself, repurposed tried to claim that shaking the Method: To make the foam, put university lab equipment for the perfect cocktail requires ‘extra- the gin, cream and egg white, cause of cocktail research, including cold ice’. But with the emergence juice and syrup into the tin half of employing mass spectrometry of cocktail science, that notion has a Boston shaker (one that uses a techniques to analyse for the been put to bed. O’Neil highlights glass instead of a lid). Blend for 20 presence of different congeners – the work of Eben Klemm, previously seconds whilst lifting the blender to chemicals like esters and aldehydes at Massachusetts Institute of incorporate air. Add a scoop of ice, that are produced in small quantities Technology in Cambridge, US, now cover and shake for 30 seconds. during fermentation and can change a full-time cocktail developer, in Strain the drink (no ice) into a tall the taste. As it turns out, there’s little dispelling the myth. chilled glass containing the soda and difference between most of the major ‘What happened was an ice flower water. brands of vodka in terms of these company was promoting its ice as flavour compounds, despite what 36 | Chemistry World | December 2010 www.chemistryworld.org their marketing suggests. tide has swung back in favour of it Dripping sugary iced Classic French absinthe The trend for molecular level just being extreme alcohol poisoning water into absinthe analysis and design of drinks has which is doing those things, but causes a ‘louching’ effect 1 sugar cube already caught on under the guise of there are still open questions in as oils precipitate 30ml absinthe ‘molecular mixology’, duplicating chemistry and pharmacology about Iced water what molecular gastronomists are it,’ says Sella. doing in the kitchen. In the UK, Method: Place the sugar cube mixologist Tony Conigliaro of The The universe in a glass on a flat, perforated spoon. Rest Drinks Factory and Andrea Sella, Although Sella and Conigliaro’s show the spoon on the rim of a glass a chemist at University College is intended to entertain, there is some containing the absinthe. Slowly London, collaborate on a show called quite serious science going on behind drip the iced water onto the ‘The Science of Cocktails’. Sella’s the scenes. Under the eaves of a house sugar cube. The sugar–water will favourite trick is to demonstrate in Islington, above his bar, Conigliaro gradually drip into the absinthe, the slow drip of ice cold water into is currently kitting out a very turning it from amber to a cloudy absinthe, resulting in the ‘wonderful cramped cocktail lab with various pale green colour as the oils louching effect’ that occurs as pieces of scientific equipment. precipitate out. terpenes in the spirit precipitate out There, he’s been experimenting of solution – surprising because both with hydrosols – products from water and absinthe are clear liquids. steam distillation of plants – and has including a chamomile cooler that’s Incidentally, the classic French recently worked out how to get a topped with fizzing foam. The foam absinthe (known as la fée verte or more flavourful extract, from mint for is made by putting gelatine through the ‘green fairy’), is one of the few instance, by adding salt. a siphon of nitrous oxide, which, cocktails – if it can be so called – Conigliaro is quite the poster unlike carbon dioxide, doesn’t cause that has actually appeared in a few boy for molecular mixology, having the pH to drop. scientific papers, mainly because picked up a prize for International There’s absolutely no doubt, says of the debate over its supposed Bartender of the Year at last year’s Sella, that molecular mixology is hallucinogenic properties.1 One of New Orleans cocktail awards. capable of producing some exquisite the culprits is thought to be a terpene At Shochu Lounge, in London’s cocktails. For Sella, though, it’s never called thujone, a not-so distant West End, Conigliaro has served really been about the drinks. ‘I’m not relative of menthol. ‘Recently the up cocktails of his own design, a big cocktail drinker to be honest,’ he says. ‘To me, the cocktails are kind of the universe in a glass – they’re the Layering liqueurs means by which you can talk about all sorts of interesting things.’ Liqueurs can be layered in the List of liquers by density O’Neil, however, is of the opinion glass based on their density,  Cream that, sometimes, you just have to with stunning effects. A  Kirsch let the drink do the talking. There ‘chocolate-covered cherry’  Sloe gin comes a point, he says – presumably for instance, layers Bailey’s  Cointreau after the cocktail has been shaken over denser Tia Maria over  Grand Marnier to perfection and is standing on the heavy Grenadine. This list  Brandy bar – when words are no longer provides a guide – those  Flavoured schnapps necessary. ‘You know, it’s fun when higher up should float on  Sambuca people are curious,’ he says. ‘But at the denser liqueurs further  Campari the end of the day, people just want down. However, density  Tia Maria to enjoy their drink.’ varies with brand,  Amaretto so – purely in the interests  Crème de menthe Hayley Birch is a science writer of scientific endeavour,  Kahlua based in Bristol, UK of course – it’s best to  Grenadine experiment.  Crème de cassis Reference 1 D W Lachenmeier et al, Forensic Sci. Int., 2006, 158, 1 (DOI: 10.1016/j.forsciint.2005.04.010) www.chemistryworld.org Chemistry World | December 2010 | 37