Beetle larvae, such as mealworms, are often considered creepy nuisances. But these insects are edible and can be a healthy alternative to traditional meat protein sources. Today, researchers report that they have cooked mealworms with sugar, creating a “meat-like” flavor. One day it can be used in suitable foods as a tasty source of additional protein.
The researchers will present their results today at the fall meeting of the American Chemical Society (ACS).
“Recently, eating insects has become of interest due to the rising cost of animal protein as well as related environmental issues,” says In Hee Cho, Ph.D., the project’s principal investigator.
According to the United Nations, the global population is expected to reach 9.7 billion people by 2050 and nearly 11 billion by 2100. And feeding everyone meat from animals — especially cows, pigs and sheep — will require more large food, water and land resources. In addition, cows are a significant contributor to climate change, releasing copious amounts of methane into their mouths. So, more sustainable sources of protein are needed.
“Insects are a nutritious and healthy food source with high amounts of fatty acids, vitamins, minerals, fiber and high-quality protein, which is like that of meat,” says Cho, whose team is at Wonkwang University. (South Korea).
But mealworms suffer from an image problem, she says.
In many parts of the world, eating insects is not common and people may be shy about eating them. Although some companies are trying to change people’s minds by selling whole cooked worms as crunchy, salty snacks, consumer acceptance is not widespread. Cho says that to get more people to eat mealworms regularly, a more stealthy approach may be needed — hiding the bugs in the form of spices inside easy-to-cook and other products comfortable.
The research team’s first step was to understand the taste profile of this insect. They compared the scents of the mealworm throughout its life cycle, from eggs to larvae to feathers to adults. While there was some variation in individual compositions, all phases primarily contained volatile hydrocarbons, which evaporate and emit odors. For example, raw larvae had odors similar to wet earth, similar to shrimp, and sweet corn odors.
Then Hojun Seo, a graduate student on Cho’s team, compared the flavors that developed when the larvae were cooked using different methods. Steamed mealworms developed an even stronger sweet corn-like flavor, while the roasted and fried versions had attributes similar to shrimp and fried oil. According to Seo, the flavor compounds from roasting and frying included pyrazines, alcohols and aldehydes and were similar to compounds formed when meat and seafood were cooked.
Based on these results, the team expected that additional reaction aromas could be produced by protein-rich mealworms if they were heated with sugar. Reaction flavors, sometimes called process flavors, are produced when proteins and sugars are heated together and interact, for example, through Maillard, Strecker reactions, and the caramelization and oxidation of fatty acids, Cho says. The result is usually an array of “meat-like” and delicious flavors.
Hyeyoung Park, a graduate student in Cho’s lab and a presenter at the meeting, tested different production conditions and ratios of mealworm powder and sugars, producing multiple versions of the reaction flavors. She identified a total of 98 volatile compounds in the samples. The team then took the samples to a panel of volunteers to provide feedback on which had the most favorable “meat-like” smell. “As a result of this study, 10 of the feedback flavors were optimized based on consumer preferences,” says Park.
To the best of the researchers’ knowledge, this is the first time that mealworms have been used to produce desirable feedback flavors. They hope these results will contribute to the commercial development of meat-like and palatable flavorings and seasonings and encourage the convenience food industry to include edible insects in their products, Cho says. The team’s next step is to further optimize the cooking processes to reduce any potentially undesirable or off-flavors in the final flavoring material made from mealworms.
The researchers acknowledge support from the Rural Development Administration (South Korea) and Wonkwang University (South Korea).