Edible insects, like ants, are considered a delicacy in many cultures, as well as being very nutritious and an environmentally sustainable source of protein. But many of us have a longstanding aversion to consuming insects. In hopes of changing that aversion, chemists at San Diego State University (SDSU) have analyzed the flavor profiles of different ant species and found that not all edible ants taste alike, according to their presentation at a meeting of the American Chemical Society in New Orleans.
Several years ago, French chef David Faure created an insect-based tasting menu at Aphrodite, his Michelin-starred restaurant in Nice. Adventurous diners could sample "crickets in a whiskey bubble with cubes of French toast and pears" or "squares of peas, carrot foam, and mealworms." The Michelin critics didn't share his enthusiasm for insect haute cuisine and took away his Michelin star in 2014. Aphrodite closed its doors for good in 2016.
Faure's gambit might have failed, but a 2018 study suggested that he had the right idea about appealing to Western diners' love of luxurious indulgence, presenting the fare as an exotic delicacy rather than as an environmentally sustainable protein source. (Food production accounts for as much as 25 percent of greenhouse gas emissions, with much of that due to livestock. Farming insects could reduce those emissions significantly.)
Specifically, Swiss scientists found that ads that emphasized the pleasurable aspects of eating insects proved far more effective at influencing participants' willingness to eat a mealworm-stuffed chocolate truffle. Those same participants also rated the taste much higher than people who tried the truffle but saw the ads emphasizing health or environmental benefits. It seems our aversion to eating bugs is emotional rather than rational. So appealing to emotions is a better marketing strategy if the goal is to change consumer behavior.
Liu has picked up the torch for changing the hearts and minds of Western diners after spending a summer doing field work in Oaxaca, Mexico, where the local markets regularly offer various edible insects along with other food ingredients. They're often used to add texture and flavor to dishes and sauces. So Liu decided to explore the different flavor profiles of common edible insects, given the dearth of prior research on the topic. The goal is to help chefs figure out ways to mask undesirable flavors or odors while boosting the more appealing notes.
Liu and a colleague, Selene Alvarado Martinez, focused on analyzing the odor profiles of queens from four species using a gas chromatography-mass spectrometer: the common black ant, the chicatana ant, the spiny ant, and the weaver ant. Once the volatile organic compounds had been identified, they were compared to odors detected using an olfactometer. Some volatiles didn't match any detectable odor and turned out to be ant pheromones used for communication that humans can't sense. But other odors were more readily identified.
Martinez was surprised to find that some of the flavor compounds she identified smelled more tropical, like coconut. "It goes to show how complex the flavor profiles of these edible insects are," she said. For instance, weaver ants smelled nutty and sweet, like caramel, offset by less desirable notes of hay and urine. Chicatana ants also have nutty notes, as well as wood and grass. The latter is due to aldehydes, which the ants use as a trail pheromone, while the nut and wood notes are attributable to pyrizines (more trail pheromones), which are also produced in cooked meats and baked bread.
By contrast, common black ants contain a lot of formic acid, secreted from venom glands, conferring a sour, sharp, and vinegary flavor profile, as well as alkanes (alarm pheromones). That makes them good for, say, replacing lemon slices or lemon juice in dishes. (Ars Science Editor John Timmer gave high marks in 2018 to black ants sprinkled on shrimp for just this reason.) Adult spiny ants also have a lot of formic acid, but it's not present at the pupa stage because the venom glands have not yet developed.
Liu next hopes to analyze more ant species to determine their flavor profiles, as well as ant eggs and male ants (drones). Different processing methods might also affect the flavor profiles, so that, too, is something for further exploration.
"It’s also very important for us to collaborate with chefs, with the culinary experts, to develop different recipes with these different insects," said Liu. "There’s a lot of things we need to pay attention to. What kind of foods can these insects be paired [with] to best bring out their flavors? So I think a lot of collaborations with the culinary arts is very important to promote insect consumption." He added, "I don't want people to feel that they are making a sacrifice by eating these insects. I want to show that they can actually taste very good, while being nutritious and good for the environment.”
