Can you possibly create the perfect dining experience for someone?” says Jozef Youssef, when we met in a Pret a Manger off Hanover Square. “Can you knowingly do so?” It’s an apt location. The thoughtful, eloquent Youssef believes chefs could learn a thing or two from the high street and we’re sat in a showcase of consumer seduction, from the packaging that loudly shuns sell-by dates in favour of more emotive “freshness” to the name above the door with its hint of continental chic. “The world now is all about experiences,” he says. “In order to craft and design that experience [chefs] have to do what all your Starbucks and McDonalds of the world are doing and that’s understanding the psychology of your diners.”
Having worked at the Dorchester, Hélène Darroze at the Connaught and the Fat Duck, Youssef is unusual for a chef. He doesn’t want to open a restaurant. Or a pub. Or even a street-food van. He’s thrown in his lot with Oxford professor Charles Spence to probe the psychology of diners and learn what pushes their buttons – off the plate as well as on. The result is Youssef’s brainchild, Kitchen Theory, a project that probes everything from the influence of sound on diners’ perceptions of a meal to how best to persuade guests to embrace unexpected ingredients – insects included. It’s a symbiotic relationship, with Spence’s work inspiring Youssef’s menus, and surprising results from Youssef’s pop-up dining “experiences” pointing to new avenues and approaches for Spence’s lab.
Three weeks earlier I found myself sat at a long table in a dimly lit room in Maida Vale, London, apprehensively awaiting Kitchen Theory’s “Synaesthesia” experience. A seven-course dinner, it promised to reveal the many ways in which our senses interact when eating.
It’s a slightly deceptive title. Only around 4% of the population are synaesthetes – individuals who experience a unique and spontaneous association between senses, such as seeing a certain colour when a specific musical note is played. The familiar multisensory nature of flavour – incorporating sight, sound, smell, taste and touch – is different, and, says Spence, more of a “blending” of the senses. “A common definition of synaesthesia would be an idiosyncratic condition,” he says. “Synaesthesia stays the same over life, whereas flavour, likes and dislikes change over time.”
The amuse bouche was four spoons, each filled with a colourful bubble of membrane-bound fluid. Our task was to match them with four anticipated flavours. A quick shuffle later and the majority of the room had opted for the same arrangement, matching red with sweet, green with sour, white with salty and brown with bitter. As the bubbles burst in our mouths, the latter rupturing forth the unmistakable notes of Guinness and chocolate, faces beamed in triumph.
And so it went on, dish after dish probing the impact of music, aerosol sprays and even the feel of textured cubes on our gastronomic expectations and perceptions. Yet for all the quirky presentation and edible surprises, our interpretations were often similar. Were we secretly culinary geniuses? Had someone glimpsed a crib sheet? Or were we simply too polite to disagree?
It turns out we were nothing special – yet it is that very intuitive agreement that Youssef aims to probe. “If it is something that we both agree on, why? If it is something that we disagree on, why?” he says. It’s research that could influence not only the presentation of fine-dining dishes, but also everyday foods and perhaps even shape what we eat in the future.
Youssef is not the first foodie to mess with minds in an attempt to unpick and augment our dining experiences. Heston Blumenthal has long been interested in the multisensory nature of eating and it was working with Spence that led to his signature dish “The Sound of the Sea” – a selection of seafood served with an iPod mini and seaside soundtrack.
Neither is Spence alone – although he is a leading figure in what’s a growing field. Among its many studies is one from 2003 in which researchers from New Zealand probed the influence of colour on the aroma of wines. Connoisseurs and casual drinkers were given four types of wine, one white, one golden and two red. What they didn’t know was that three of the wines were the same and only one of the reds was the real thing: the scientists had been tinkering with a food colouring. It turned out that both experts and novices were baffled. For the experts, words typically linked to pinot noir, such as plummy or berry-like, scored higher ratings when it came to describing the bouquet of the red-tinted sample than for the other samples of the same wine; the effect diminished when the wines’ colour was obscured. Social drinkers meanwhile were poorer all round at judging wine aromas and haphazardly described the red-tinted sample with both red and white wine-related words.
As for sound, in 2010 researchers from the food giant Unilever discovered that loud white noise can affect the taste of food, sapping both sweetness and saltiness, while Spence and his team have also explored associations between pitch and taste, finding sweetness and sourness to be correlated with high-pitched sounds, while bitterness could be augmented by low-pitched sounds. Even tactile experiences sway us – serving a dish with high quality, heavy cutlery, Spence has found, can increase how much restaurant diners like it and the amount they are willing to pay for it.
And Instagrammers beware: a small 2012 study suggested that looking at images of high-calorie food is linked to a rise in levels of an appetite-inducing hormone, while research the following year found that looking at images of salty foods decreased enjoyment of eating a salted snack.
A showman as well as scientist, Spence has a knack for the kind of research-based nuggets of information that might intrigue not only journalists but food and drink companies seeking competitive advantage in a crowded marketplace. For example, in a recently published study, Spence and colleagues discovered that adding swirls of “latte art” to coffee resulted in subjects being willing to pay 11-13% more for the drink.
Some companies have been attempting to harness our senses for a while. Five years ago, Heineken unveiled a textured beer can with a raised surface that the company claimed made the can more tactile, boosting the appeal of the drink inside. In 2012, McCain also went multisensory, wooing the public by pumping the smell of jacket potatoes into bus shelters and, the following year, through the frozen food aisles of Asda and Tesco.
However, employing psychology for profit is riddled with potential traps. While flavour might be multisensory, the associations we make between our senses are not necessarily a foregone conclusion. When presenting subjects with a brown drink, Spence and colleagues discovered that the majority of youngsters sampled from the UK expected a cola taste, while those from Taiwan were most likely to expect it to taste of grape. Links between flavour and shapes or word-sounds aren’t universal either. For westerners, bulbous shapes and soft-sounding words such as “bouba” are typically matched together and with fatty or sweet foods, while bitter and sour flavours are linked to sharp and angular shapes and sounds such as “kiki”. But not everyone agrees. “We have been giving dark chocolate and carbonated water to the Himba tribe in northern Namibia,” says Spence, who believes the associations we make are largely a matter of experience. “Do they, with no schooling, think also that bitter is angular? And they don’t.”
Youssef insists there’s much more to his work than helping big companies make money and providing exotic experiences for the well-heeled. “People say, ‘What the hell does it matter if a red strawberry mousse is rated as being 10-12% sweeter if you put it on a white plate than on a black plate? Who cares outside of some pretentious chef, some pretentious diners?’” he says. But he’s adamant that employing lessons from psychology could allow producers to create healthier foods. Altering the colour of foods and packaging, for example, could enable a reduction in sugar content. “Now we are starting to tackle obesity, diabetes and lots of other health-related issues that come from sugar. So where is the pretension in that?” says Youssef.
It’s not such a wild idea. In 2012, Cadbury unveiled its new Dairy Milk bar, its previous hard edges replaced by a curvier configuration. Complaints followed, most of them concerned not with the way it looked but how it tasted. Consumers were convinced it was sweeter, yet Cadbury’s maintained the recipe hadn’t been tinkered with. Spence believes it’s a case in point of shape influencing flavour, and he thinks Cadbury’s missed an opportunity. “[You’d] think there would have been a health opportunity to reduce the amount of sugar – change the shape and keep the perception in the mind of the consumer exactly the same,” he says.
But for Spence and Youssef, a bigger challenge lies in persuading us to try something we believe to be repulsive but might ultimately be beneficial – such as eating insects and worms as a cheap source of protein. It’s an area Youssef is already starting to explore, presenting guests at the Synaesthesia dinner with sourdough and two types of butter: one salted, the other containing dried worms. Thinking it would be rude not to try, I had gingerly placed a dab on the bread. It tasted like, well, butter – although the worms added a certain coarseness. As I later confess as much to Youssef he looks triumphant. “People don’t want to eat insects, but we know they are more sustainable and very high in nutrition,” he enthuses. Fatty, familiar, malleable butter, he believes, is an excellent medium for lulling diners into an adventurous mood. And it seems to be working. “On the random spot-checks we’ve done, we get more salt butter than worm butter back,” he reveals. Although the appeal isn’t universal. “I have had a guest sit down, look at the menu, get served worm butter, stand up and say, ‘This isn’t for me.’”
Professor Terry Acree of Cornell University believes appeal might simply be a matter of experience and exposure, explaining the attraction of durian fruit despite its pungent odour. “Those are sulphur compounds which are scatological in nature, they are found in poop,” he explains. “Those compounds are very strong and very intense and associated with some pretty bad stuff – but you adapt to them very quickly.”
Other useful applications seem possible, with Spence keen to apply his insights to hospitals, finding ways to tackle the metallic taste of food often experienced by cancer patients, or make medication more appealing by experimenting with fake capsules produced in the kitchen. “It’s just a bitter tasting pill – but from that we can see which shapes and colours and combinations and what names [to use],” he explains. Spence even envisages harnessing multisensory stimuli to help those with Alzheimer’s. “We are thinking about olfactory alarm clocks that release the scent of meals three times a day to remind them to eat,” he explains. And with an ageing population, employing all of our senses to bolster our experience of flavour could make getting older more palatable, too. “You’ve got hearing aids and glasses for the other senses but nothing for smell,” Spence points out.
But if teasing apart the factors that influence flavour is one challenge, reassembling them into a truly remarkable dining experience is quite another. In one attempt, exploring Nordic cuisine, Youssef exposed diners to birdsong and rustling trees, scenes from Scandinavia and the scent of wet earth while they ate a nature-inspired dish – a fusion, he says, that bolstered diners’ memories of the food itself by employing all the senses.
Indeed, Youssef believes embracing our multiple senses could offer a new recipe for success. “As a chef, when you look at your senses you think of them as individual parts and the dining experience as the sum of the parts,” he says. “What you never think is one plus one equals three.”
