Gastrophysics: The New Science of Eating by Charles Spence; Viking, 336 pp., $27
For several days in April, the American media took a break from their around-the-clock coverage of President Trump’s first 100 days to comment on another outsider with unnatural coloring: the Unicorn Frappuccino from Starbucks. Much of the criticism-cum-comedy focused on several of the drink’s ingredients—pink powder, blue drizzle, sour blue powder topping—that Starbucks unabashedly promoted via its PR machinery.
“When a news release identifies a drink’s component parts by its colors, rather than its flavors—well, that’s a pretty telling detail,” wrote one of my colleagues at The Washington Post. Late Show host Stephen Colbert piled on: “That’s all your food groups right there: Mango, pink, blue, and obviously, topping. The FDA recommends at least three servings of topping a day.”
Turns out, the joke may be on us. According to the research conducted by Charles Spence and his colleagues in the field of gastrophysics, people actually do associate colors with basic human tastes. In one experiment that Spence shares in his playful, approachable book, Gastrophysics: The New Science of Eating, diners were asked to arrange four sample spoons, each containing a small sphere of colorful liquid, in the exact same order: the salty one first, followed by the bitter one, the sour one, and finally the sweet one. Diners had no clue what the liquids contained. They knew only the colors: red, white, green, and brown-black. (Ask yourself what tastes you would assign to each color and compare them with the answers below.) In the test, “we get somewhere around 75% of people ordering the spoons in the way that the chef (and the gastrophysicist) intended,” Spence writes. “So on the basis of such results, I would say that tastes are very definitely associated with specific colors.”
The experiment is further confirmation of what gastrophysicists have long been telling chefs, restaurateurs, and regular diners: Our experience with food is not shaped by taste alone, or even taste in combination with smell. All our senses work in tandem to heighten our pleasures, alter our opinions, and sometimes convince our brains that a foodstuff is fresher, sweeter, or more filling than it really is.
A merging of gastronomy and psychophysics, gastrophysics is, writes Spence, “the scientific study of those factors that influence our multisensory experience while tasting food and drink.” That, mercifully, arguably, is the wonkiest sentence in the book. A professor of experimental psychology at the University of Oxford and head of the school’s Crossmodal Research Laboratory, Spence takes pains to rise above the academic language of his field to explain his research clearly, often humorously, while providing examples of how it applies in the real world.
Chapter after chapter, Spence runs through our primary senses, providing food for thought all along the way. Have you ever wondered why some fine-dining chefs serve an entrée with a side dish of pure aroma, such as the pheasant at Alinea in Chicago, which comes atop a bowl that wafts scents of hay, apples, and cinnamon? It’s not because we mostly “taste” through our nose. It’s because our sense of smell is closely tied to memory and emotion. With his pheasant, Alinea chef Grant Achatz is feeding our nostalgia as much as our hunger, hoping our associations with fall are warm enough to intensify our feelings toward his dish.
“It turns out that the olfactory receptors in our nose are actually an extension of our brain,” Spence writes. “In fact, it is only a couple of synapses from the cells in the olfactory epithelium lining the inside of the nose through to the limbic system, the part of the brain that controls our emotions.”
Spence’s research can be applied to both the restaurant and the grocery store. His famous study—for which Spence and a colleague were awarded an Ig Nobel Prize for Nutrition in 2008 by the scientific humor magazine Annals of Improbable Research—concerns a sonic experiment in which volunteers were asked to chomp on potato chips in front of a microphone, which directed the sound back to the participants’ headphones. Unknown to the chip eaters, researchers were manipulating the sounds. Volunteers perceived the chips to be fresher and crunchier when sampled under higher frequencies, their ears clearly influencing their taste buds. Perhaps more remarkably, Spence later discovered that just by increasing the noise of the packaging, he could alter people’s perception of how crunchy the chips were inside. “[O]ur brains appear to have a remarkably hard time distinguishing the product from the packaging,” he writes.
You can probably blame Spence and his peers for those bags of SunChips that rattled louder than an old rollercoaster. But you can also credit them for helping us understand how almost everything can affect the perceived quality of our food and drink. It could be music (“the more we like the music, the more we enjoy the taste of the food and drink”), utensil weight (“if people tasted food with a heavier spoon they generally had better things to say about it than when exactly the same food was eaten with a lighter spoon”), even product shape (“Sweet and creamy sensations … are nearly always paired with rounder shapes”).
The book is not without its faults. When Spence moves beyond the interaction of human senses, his observations are less compelling. His chapter on social dining, for example, reads more like a mental health argument against eating alone than a gastrophysics-based defense of group dining, and another on airline food includes a finding that I found comical: that in flight, pairing pasta with a Verdi aria, for example, could boost a diner’s perception of the dish’s authenticity. I mean, what functioning adult is expecting Tuscan trattoria cooking at 30,000 feet?
Gastrophysics could have also used a tougher editor. Repeated references to the Italian Futurists as the forerunners of modern molecular gastronomy grow tedious, especially when Spence offers 13 tips on how to host your own “Futurist party.” His intended audience also seems to be a moving target. Sometimes he addresses chefs and food manufacturers, and sometimes he appeals, with lesser authority, to home cooks.
Still, you have to give the man his due. Spence’s influence on the food industry is significant. You could even argue that Starbucks employed gastrophysics to the potential benefit of its customers. As Spence notes, you can “make food or drink taste sweeter by adding a pinkish-red colour.” In other words, consumers might not notice if you cut down the sugar in a drink that has the addition of, say, “pink powder.” Interestingly, the Unicorn Frappuccino had 59 grams of sugar compared with 69 grams in the same-size cup of Caffè Vanilla Frappuccino. That doesn’t exactly make the Unicorn Frappuccino a fruit smoothie, but it’s a start.
(By the way, for those keeping score, most people associate red with sweet, green with sour, white with salty, and brown-black with bitter.)