• Food Science of Animal Resources
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• v.40 no.4
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• pp.649-658
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• 2020

This study compared aroma compositions and sensory aroma attributes of raw and cooked Tenebrio molitor larvae (mealworms). Main sensory aroma attributes of raw mealworms were strong wet-soil-like, and less-intense oily, shrimp-like and sweet-corn-like. Quantitatively, the major aroma components of raw mealworms were hydrocarbons and aldehydes. As cooking proceeded, sweet-corn-like, roasted, and fried-oil-like sensory attributes were increasingly perceived with steaming, roasting, and frying, respectively. Some pyrazines, pyrrolidines, and carbonyls increased or appeared in roasted and fried mealworms. Partial least squares regression also showed differences in raw and cooked mealworms based on aroma components and their sensory attributes. Unlike raw mealworms, steamed mealworms had a relatively strong sweet-corn-like aroma attribute, which was related to 2,4,6-trimethyl-heptane, 2,4-dimethyl-dodecane, and 3,5-dihydroxy-6-methyl-2,3-dihydropyran-4-one. In comparison, roasted and fried mealworms exhibited roasted, shrimp-like, and fried-oil-like aroma attributes, which were associated with intermediates of the Maillard reaction and lipid oxidation, such as pyrazines, alcohols, and aldehydes. This result during thermal reactions was very similar to those of meat and/or seafood. The use of mealworms as a savory-type flavor enhancer can be expected.

• Journal of Bio-Environment Control
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• v.33 no.3
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• pp.172-177
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• 2024

Many studies have reported that mealworms can ingest plastic during their larval stage. The purpose of this study was to investigate the effects of expanded polystyrene consumption on the growth and development of mealworms during their larval stage. We found that the growth rate is significantly different between mealworms consumed wheat bran and mealworms consumed expanded polystyrene (p < 0.001). The transformation into pupa occurred faster among the mealworms consumed expanded polystyrene than those consumed wheat bran (p < 0.001). However, the survival rate was not significantly different between the two groups of mealworms (p = 0.786). Based on the data, we conclude that mealworms consuming expanded polystyrene have a slower weight gain and a shorter development period than mealworms consuming wheat bran, but the expanded polystyrene does not affect the survival rate before the transformation into pupa. Practically, we anticipate that mealworms can be a resource for the sustainable and eco-friendly removal of expanded polystyrene waste.

• International Journal of Industrial Entomology and Biomaterials
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• v.39 no.2
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• pp.54-59
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• 2019

Yellow mealworms (Tenebrio molitor Linnaeus) are very promising insects for the food and feed industry. Because mealworms are in the spotlight as an alternative protein source in the future, it is necessary to develop efficient rearing techniques for mass production. To evaluate the effects of brewer's yeast (BY) on the growth of mealworms, Tenebrio molitor Linnaeus, the mealworms were fed with wheat bran (WB) diets containing different levels of BY (0, 10, 30, 50, and 70%). Larval survival, larval weight, development time, pupal weight and eclosion rate were monitored for 12 weeks. The results showed that mealworms fed on the diets containing 30% and 50% of BY have significantly higher weight gain, specific growth rate and daily weight gain, and lower larval duration than fed the control diet (100% WB) and other BY diets (10% and 70% BY). Larval survival on the diets containing 30% and 50% of BY was higher than on control diet. Pupal weight and eclosion rate were not significantly different among all diets. In conclusion, we suggest feeding the diet containing 30% of brewer's yeast with wheat bran in order to increase the production of mealworms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.249-254
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• 2013

As part of a study on insects as food, the nutritional and harmful components in the mealworm (Tenebrio molitor) were analyzed. In addition, due to a recent introduction of live Chinese mealworms in the Korean market, components between Korean and Chinese mealworms were compared. Analysis of general composition (moisture, crude protein, crude fat, crude ash, crude fiber, and carbohydrates) showed that crude protein (50.32~52.79%) was abundant in both Korean and Chinese mealworm powders, with the protein content in the Chinese mealworm powder higher than that in the Korean mealworm powder by 2.67%. The amino acid compositions were similar, but the fatty acid compositions differed in the Korean and Chinese mealworm powders. The unsaturated fatty acid contents were 76.80~80.55% of the total fatty acid content in the mealworms. The linoleic acid contents in the Korean and Chinese mealworms were $20.8{\pm}1.1%$ and $34.69{\pm}1.9%$; the linolenic acid contents were 0.47% and 1.31%; and the oleic acid contents were $51.40{\pm}0.9%$ and $40.20{\pm}1.5%$, respectively. With respect to harmful components, such as heavy metals and bacteria that cause food poisoning, bacteria such as Escherichia coli O157:H7 and Salmonella spp. were not detected in both Korean and Chinese mealworms, and the mercury content was below the standard values for common foods (Korea, 0.03 mg/kg; China, 0.08 mg/kg).

• Journal of Bio-Environment Control
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• v.33 no.3
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• pp.139-147
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• 2024

Mealworms are used as food, so it is preferable if the larval stage lasts longer. On the other hand, to accelerate the population growth of mealworms, it is preferable if the larvae become adults quickly. The purpose of this study is to explore the effects of population density on development time of mealworms. We used a container size of 7 cm at the top, 5 cm at the bottom, and 3 cm in height. Mealworms lived in the containers at densities of 1, 2, 5, 10, and 20 per container. The containers were bedded with 1 g of wheat bran and formed two groups, fed and not fed, at each density levels. The experiments were performed three times. In all of the experiments, higher population densities resulted in shorter transformation times from larva to pupa, but the time from pupa to imago was not significantly different. In addition, given the same density, the presence of food accelerated the time to transformation to pupa, but not to imago. The data supported that a lower density is needed to prolong the larval stage, and if adults are needed at a faster rate, the density should be higher. Therefore, we conclude that the development time of mealworms can be controlled by the density which is useful information for mealworm farmers.

• Journal of the Korean Society of Food Culture
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• v.33 no.1
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• pp.48-54
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• 2018

This study was performed to evaluate the quality characteristics of functional Dasik prepared with a mixture of freeze-dried mealworm (Tenebrio molitor) powder and dried pollack powder along with assessment of the general and fatty acid compositions of mealworms. General compositions, except for moisture content of freeze-dried mealworm powder, were higher than those of raw mealworms. The ratios of saturated fatty acids and unsaturated fatty acids of freeze-dried mealworm powder and raw mealworms were 1:3.31 and 1:3.19, respectively. Amounts of oleic acid, which was the most abundant among unsaturated fatty acids, of freeze-dried mealworm powder and raw mealworms were 41.12 and 37.84%, respectively. For color values, greater content of freeze-dried mealworm powder in functional Dasik resulted in lower L and b scores, whereas a value increased. In the case of mechanical properties, greater content of freeze-dried mealworm powder resulted in significant reduction of hardness, chewiness, and gumminess. In the case of sensory evaluation, color, taste, and overall quality of DPMD50, which was prepared with a 1:1 ratio of freeze-dried mealworm powder and dried pollack, were the highest. It was concluded that DPMD50 is a nutritious combination of edible insects and fish for protein fortification for growth and the elderly.

• Journal of Ecology and Environment
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• v.30 no.4
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• pp.357-361
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• 2007

To determine the feeding sites preferred by adult gold-spotted pond frogs, Rana plancyi chosenica, and the foods that induce favorable growth of the frogs in the laboratory, we conducted two separate experiments between 27 May and 12 July 2007 in a vivarium. In the first experiment, we counted the number of crickets eaten by four gold-spotted pond frogs in a 60 min period at four different feeding sites within the experimental arenas: on the water surface, at the edge of a pond, and at two terrestrial sites. Adult gold-spotted pond frogs ate more crickets on the water surface and at the edge of the pond than the terrestrial sites. In the second experiment, we measured the growth of SVL (snout-vent length) and body mass of adult gold-spotted pond frogs fed crickets, mealworms, maggots, or earthworms in individual experimental boxes over a one month period. The SVL and body mass of the adult gold-spotted pond frogs fed crickets, mealworms, or maggots were greater than those of the frogs that were fed earthworms. These results indicate that providing crickets, mealworms, or maggots on the water or at the edge of a pond should induce favorable growth of captive-reared adult gold-spotted pond frogs.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.2
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• pp.194-203
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• 2017

Mealworm, a type of edible insect, is a superior food material suitable for industrial products. In this study, four different defatted mealworm powders were prepared to determine proper manufacturing conditions. Solvent extraction method reduced lipid contents of mealworms more than pressed mealworms, and lowered lipid contents caused bright colors and good physicochemical properties for powders. In comparison, differences among milling machines used for making powders were strongly related with average size of particles. Meanwhile, the predicted shelf-life of defatted mealworm powders judged by accelerated experiments was 1 year or longer. To enhance shelf-life of mealworm powders, addition of tocopherol to mealworm powders at a concentration of 0.2% could intensify oxidative stability and microbial inhibition.

• International Journal of Industrial Entomology and Biomaterials
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• v.32 no.1
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• pp.41-48
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• 2016

Mealworms, Tenebrio molitor (Coleoptera: Tenebrionidae), are widely used as food sourcefor animal rearing as well as human diet. Conventionally, mealworms raised on wheat bran. In this study, we investigated the effects of brewer's spent grain (BSG) on the growth of mealworm larvae to reduce the rearing cost. We prepared five different diets with various BSG content, 0, 10, 30, 50, and 70% of heated air dried BSG with wheat bran. We compared survivorship, larval weight, developmental duration, pupation rate, and pupal weight of five different groups of T. molitor raised on these five diets. The larval survivorships were almost similar with the control group except a group with 70% of BSG. For the larval weight, groups with 30% and 50% of BSG gained more weight than that with control treatment, 0% of BSG. For the developmental period, the groups with 30% of BSG took less time compared to the control group. In all treatment groups, more than 90% of pupation rate were observed. Especially, the group with 30% of BSG showed highest pupation rate among the five groups. Wheat bran with 30~50% of BSG was the optimal diet for successive insect rearing among the five diet treatments. Based on this study, we concluded that adding BSG to wheat bran helps to improve the quality of T. molitor and to reduce the rearing period.

• Journal of the Korean Dietetic Association
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• v.22 no.4
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• pp.292-309
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• 2016

The purpose of this study was to verify the validity of Mealworms as a hospital meal with increased nutrition density. We provided a meal for postoperative patients and conducted analysis of dietary intake and nutritional status of patients and assessment of acceptability of the meal. This study was carried out as a randomized control trial. Patients were supplied either a hospital meal using Mealworms (Experimental group) or a regular hospital meal (Control group). We investigated the administration amounts of parenteral nutrition (PN) and food intake of patients after surgery and measured anthropometry, body composition, and blood tests before surgery and at hospital discharge. We included 34 postoperative patients who were admitted to Gangnam Severance Hospital from March to September. In the groups of patients not supplied with PN, the experimental group ($964.68{\pm}284.6kcal$, $38.82{\pm}12.9g$) had significantly higher dietary calorie and protein intake than the control group ($666.62{\pm}153.7kcal$, $24.47{\pm}4.9g$)(P<0.05). Additionally in the group of patients not supplied with PN, the experimental group (1.37%) showed a significantly higher increase in fat free mass index than the control group (-3.46%)(P<0.05). In all subjects, calorie density and protein density were significantly higher in the experimental group (P<0.001), and acceptability of calorie (P=0.036) and protein (P=0.001) was also significantly higher in the experimental group. Therefore, the results of this study support the validity of the introduction of hospital meals using Mealworms.