The centerpiece of MOFAD Lab's first exhibit, Flavor: Making It and Faking It, is on the back wall of the museum's cavernous industrial space. It's a feat of invention that looks a little bit like the control panel of a spaceship, if the purpose of the spaceship were to transport you to a pancake breakfast, or to a tropical island bar, with the push of a few buttons and a puff of air through a pipe. It's called the Smell Synth.
a lot of what we think is taste is actually smell
The Smell Synth is a heavily simplified, home-built version of a sophisticated machine used by researchers at the Monell Chemical Senses Center, an institute in Philadelphia devoted to research on taste and smell. That machine, which MOFAD founder Dave Arnold and program director Emma Boast saw in action when they visited the Monell Center while planning the museum's exhibit, allows olfaction scientists — that is, smell scientists — to produce and mix smells in real time, from a catalogue of chemicals. The couple of readymade options out there would have been way too expensive and way too complicated to acquire for the museum, so Arnold, a food technologist, set out to build his own.
If you look behind the slick, white, button-clad control panel of the Smell Synth, you'll see a rainbow tangle of wires and a machine that looks a little like a tentacled pool filter, wrapped in gauzy material, with air hoses snaking up into the underside of the control panel. It's built mostly out of stuff bought at the hardware store, and in basic design it's actually quite similar to sort of filter marijuana growers use to dissipate the smell of their crop. Arnold spent a lot of time online, browsing forums, to figure out how to build it. He also spent a few weeks teaching himself computer coding, so he could program the machine to blow out the right scents in the right amounts at the right time.
Somewhere out of view are 19 different glass containers, each partially filled with a specific scent chemical dissolved in a solution. Small amounts of those chemicals end up in the air also sealed in the containers — the same way the scent of butter and sugar floods your kitchen when you bake cookies — and when you press the corresponding button, the machine opens a valve in the container and blows out that scented air through a pipe, right at your waiting nose.
Each of the 19 chemicals are as simple as smell gets, each just one of the many individual components of the complex smells we experience in everyday life. They're not something you would probably ever smell on their own if it weren't for the Smell Synth, and yet they're all vaguely familiar, all like something you might eat (a lot of what we think is taste is actually smell, which is why the Smell Synth even exists in an exhibit about taste). Press multiple buttons at once, like playing a chord on an organ, and you can combine scents to mimic a more familiar smell, like pancakes with syrup, or orange soda.
Each button on the smell synth is labelled with a descriptors — "ripe fruit," "cheesy vomit" — sort of like gonzo wine descriptions. Settling on these labels was almost as hard as the crash course in computer programming. The job fell to Emma Boast and program associate Catherine Piccoli, who both spent hours dipping blotter strips into jars of chemicals, sniffing them with the attention of a sommelier, trying to describe the scent. Chemicals like cinnamaldehyde, the thing that makes cinnamon smell like cinnamon, were easy. Others, like linalool, a chemical found in many herbs and spice plants, were hard to pinpoint. Sometimes it smelled like lavender, other times like something else, which after many sniffs Boast pinpointed as toasted coriander seeds. In this case, a little research confirmed what a sommelier would never be able to: linalool is found in coriander, so Boast was in fact exactly right. "If I were to redo it," she says, "I might even consider using washes of color to describe each smell. Smell is abstract, it's hard to describe with words."
Up on the wall above the Smell Synth's control panel is a web of different scent chords you can play — recipes for which buttons to press the get the (still notably artificial) smell of coconut rum, for example, or cherries. But there are, of course, way more possibilities than the ones given. Boast and Piccoli have designed some recipes, for scents like pina colada, and smoked almond, which are now included in a museum scavenger hunt visitors can get when they arrive. Some of their recipes even involve even involve the flavor tablets being dispensed from gum ball machines on another wall of the museum. But flavor design is also something any visitor to the museum can do, just by following their nose.