The larvae of beetles, such as mealworms (Tenebrio molitor), are often considered scary and disgusting. But these bugs are edible and can be used as a healthy alternative to traditional animal protein. Now, researchers have announced that they have made a meat-like seasoning with mealworms and sugar. One day, it can be added to convenience foods and become a delicious alternative source of protein.

The researchers presented their findings at the fall meeting of the American Chemical Society (ACS), held Aug. 21-25.

"Currently, edible insects have generated interest due to the rising cost of animal protein, as well as the associated environmental concerns," said Dr. In Hee Cho, the project's principal investigator.

According to the United Nations, the global population is expected to reach 9.7 billion by 2050; It will reach nearly 11 billion by 2100. The animal meat needed to feed these populations, especially cattle, pigs and sheep, requires large amounts of food, water and land resources. In addition, cow burps excrete large amounts of methane, which is a significant contributor to climate change. As a result, there is a need for more sustainable sources of protein.

"Insects are a nutritious, healthy food source that, like meat, contains a lot of fatty acids, vitamins, minerals, fiber, and high-quality protein," said Dr. Cho of Wonkwang University in South Korea.

But mealworms have an "image problem".

In any parts of the world, it is unusual to eat insects, and people may feel sick to chewing on insects. While some companies are trying to change people's minds and sell cooked whole mealworms as a salty and crispy snack, it is still not universally accepted by consumers. Cho says that in order to get more people to eat mealworms, there may be a more subtle way to hide the insects in the form of seasonings in easy-to-cook foods and other convenience foods.

The first step for the research team was to understand what the insect tastes like.

They compared the taste of mealworms throughout their life cycle, from eggs, larvae, pupae to adults. Although there are certain differences in the substances at different stages, all stages mainly contain volatile hydrocarbons, which emit odors. For example, the raw larvae have the smell of moist earth, shrimp and sweet corn.

After that, Hojun Seo, a graduate student from Cho's team, compared the flavors produced by mealworm larvae when cooked in different ways. Steamed mealworms will give off a richer sweet corn flavor, while roasted and fried mealworms will have a shrimp flavor and fried flavor. According to Seo, the flavor substances produced during the process of grilling and frying include pyrazine, alcohol, aldehydes, etc., similar to those produced when cooking meat and seafood. Based on these results, the team predicted that heating protein-rich mealworms with sugar could produce additional reaction flavors.

Reactive flavors, also known as processed flavors, arise from interactions that occur when proteins and sugars are heated together, such as Maillard, Steclay, caramelization, and fatty acid oxidation, Cho says. The result is usually a range of meaty and salty flavors.

Hyeyong Park, a graduate student and conference speaker at Cho Lab, tested different reaction conditions and different ratios of mealworms and sugars to produce a variety of reactive flavors. She identified a total of 98 volatile compounds in her samples. The team then gave the samples to a group of volunteers who asked them to give feedback on which sample gave off the best "meaty taste." "Ultimately, the study optimized 10 reactive flavors based on consumer preferences." Park said.

As far as the researchers know, this is the first time that mealworms have been used to produce the ideal reaction flavor. Cho said he hopes the findings will help commercialize meaty and savory seasonings and encourage the convenience food industry to include edible insects in their products. As a next step, the team will further optimize the cooking process to reduce any undesirable flavors or off-flavors in the condiments that mealworms end up making.

Research information

【Title】 Comparison of aroma profiles from mealworm (Tenebrio Molitor)-based reaction flavors optimized by consumer preferences.

【Abstract】 Mealworm (Tenebrio Molitor), which contains beneficial essential amino acids and is high in unsaturated fatty acids, is one of the most widely used edible insects in the world. However, edible insects are not universally accepted in our food cultures due to their repellant appearance and unique flavor characteristics. Therefore, many studies have been conducted on various processed food applications with mealworm. Our previous study had demonstrated the possibility of manufacturing mealworm-based reaction flavor (M-RF); the present investigated aroma profiles and the differences between M-RFs optimized by consumer preferences. A total of 98 volatile compounds were identified in M-RFs, including 17 nitrogen-containing heterocyclic compounds, 9 oxygen-containing heterocyclic compounds, 8 sulfur-containing heterocyclic compounds, 11 sulfides, 15 aldehydes, 6 ketones, 11 alcohols, 13 esters & acids, and 8 aliphatic hydrocarbons. The differences in M-RF aroma profiles were modeled using partial least squares-discriminant analysis. This indicated that M-RFs exhibiting larger amounts of methionine and garlic powder were located on the positive t axis, while those with higher proportion of cysteine were on the negative t axis. The main compounds contributing to this separation were linoleic acid ethyl ester, 2-pentylfuran, benzeneacetaldehyde, ethyl palmitate, benzaldehyde, ethyl oleate, 2-ethyl-3,5-dimethylpyrazine, and tricosane. Our model also revealed that M-RFs exhibiting higher proportion of garlic powder were located on the positive t axis, while those with more methionine were on the negative t axis. Ferruginol, diallyl sulfide, eugenol, 2-methyl-3-furanthiol, 2-furfurylthiol, 3-methyl-2-thiophenecarboxaldehyde, 1-hexanol, 2-nonen-4-one, allyl propyl sulfide, diallyl trisulfide, allyl prop-1-enyl disulfide, and 4-heptenal were associated with this discrimination.