The yellow mealworm, Tenebrio molitor, occupies a peculiar dual role in human affairs. It is a notorious pest that infests stored cereal products, yet it is simultaneously one of the most valuable and nutritionally rich insects used in both animal and human food industries. Researchers describe it as a beneficial pest precisely because of this contradiction. Beyond its agricultural significance, the species can degrade polystyrene and plastic waste, making it an object of interest for waste management research, and it serves as a model organism in laboratories worldwide.

Gregarines are parasitic protozoans belonging to the phylum Apicomplexa, a group that includes some of the most notorious parasites of invertebrates. These single-celled organisms colonize the digestive tracts of many different insect species, and their effects on hosts have proven remarkably complex. Numerous experimental studies have documented both detrimental and beneficial outcomes. On the harmful side, gregarines can arrest host development, cause mortality, and inhibit reproduction. On the beneficial side, some studies have shown they can increase host growth, fitness, and longevity, complicating any simple assessment of their ecological role.

The research team dissected forty larval and forty adult mealworms from each location, examining their intestines under microscopes at magnifications ranging from 10x to 1000x. When parasitic infections were observed, the scientists prepared Giemsa-stained smears to visualize the parasites in greater detail. The slides were air-dried, fixed with methanol, and stained with a freshly prepared 5 percent Giemsa solution before re-examination. The team then measured key anatomical structures of the parasites, including the length of the epimerite, deutomerite, and protomerite, along with total body length and various width ratios that help distinguish between gregarine species.

The results revealed a dramatic contrast between the two populations. In the Tbilisi samples, gregarine infection was present in both life stages, with several life stages of the parasite found in the midgut lumens of larvae and adults alike. Each trophozoite was elongate with a bud-type epimerite measuring 5.5 micrometers, and the largest trophozoite observed reached 67.9 micrometers in length. The sporadins found in the midgut lumen were solitary, with a clearly distinct septum separating the protomerite from the deutomerite, and the deutomerite was ovoid to ellipsoid with a spherical nucleus averaging 10.3 micrometers in diameter.

Infection rates differed sharply between life stages. Twenty-nine of the forty examined larvae were infected, representing a 72.5 percent infection rate, while only seven of the forty examined adults carried the parasite, corresponding to just 17.5 percent. This substantial difference suggests that mealworm larvae are considerably more susceptible to gregarine infection than adults, a finding that carries practical weight for insect farmers who rear larvae as the primary product for food and feed applications.

In stark contrast, the Antalya population from Türkiye showed no gregarine infection whatsoever, neither in larvae nor in adults. This complete absence of the parasite in one geographic population while another shows high infection rates raises intriguing questions about how gregarines spread within and between insect colonies, and what environmental or management factors might explain such divergent outcomes between facilities located in different countries.

To identify the parasites, the researchers compared their morphological measurements and ratios against a well-documented comparative study by Clopton and colleagues from 1991, which described the morphology and general appearance of gregarine species infecting T. molitor. According to a recent review of harmful and beneficial symbionts of the mealworm, four eugregarine species are known to infect this insect: Gregarina cuneata, G. polymorpha, G. niphandrodes, and G. steini, with G. cuneata considered the most impressive and complex among them. The parasites found in the Georgian population resembled both G. cuneata and G. niphandrodes in body morphology and general appearance, yet they differed from published descriptions in their morphological measurements and ratios.

This discrepancy becomes particularly interesting when considering host stage specificity. Clopton and colleagues reported that G. polymorpha and G. steini are found only in mealworm larvae, whereas G. niphandrodes was reported only from adults. Gregarina cuneata, by contrast, infects both larvae and adults. Because the Georgian parasites were detected in both life stages, the researchers suggest that more than one gregarine species might be infecting the Georgian population, or that multiple species could coexist within the same individual host. The possibility even remains that a previously unknown gregarine species could be identified from Georgian mealworm populations.

The findings arrive at a critical moment for the edible insect industry. High-density rearing conditions associated with mass production may increase the risk of disease and infections by parasitic symbionts, promoting their spread within insect colonies. These pathogens could potentially be passed to humans and animals consuming mealworms as food, making parasite surveillance a food safety concern as well as a production issue. The researchers call for further characterization of the gregarines in Georgian mealworm populations, including molecular phylogeny studies, and recommend documenting the presence and distribution of these parasites across other Georgian populations. Such work will be essential for understanding whether the parasites represent a threat to commercial production or simply another facet of the complex biology of an insect that humanity increasingly relies upon for sustainable protein.

Subject of Research: Gregarine parasite infection in yellow mealworm populations in Georgia and Türkiye

Article Title: Occurrence of gregarine parasites of Tenebrio molitor ( Coleoptera : Tenebrionidae ) in Georgia and Türkiye

Article References: Yaman, M., Kereselidze, M., & Güvendik, T. S. (2025). Occurrence of gregarine parasites of Tenebrio molitor (Coleoptera: Tenebrionidae) in Georgia and Türkiye. Caucasiana, 4, 119-124. https://doi.org/10.3897/caucasiana.4.e164996

Image Credits: AI Generated

DOI: 10.3897/caucasiana.4.e164996

Keywords: gregarine parasites, Tenebrio molitor, yellow mealworm, Apicomplexa, insect farming, edible insects, Georgia, Türkiye, parasitology, food safety, entomology, sustainable protein

The scale of insect consumption worldwide is staggering. More than 3,000 ethnic groups eat insects, and 2,205 species have been documented as food across 128 countries. In Africa alone, 464 edible species have been reported from 48 countries, with termites, caterpillars, crickets, and grasshoppers among the most widely consumed. Yet while insects deliver high-quality protein, lipids, vitamins, and minerals, the safety landscape surrounding them has remained surprisingly underexplored—particularly when they are incorporated into foods for the most vulnerable consumers: infants and young children.

To fill this gap, the research team analyzed 30 material types: 11 edible-insect products, seven food ingredients, seven insect-enriched formulations, and five commercial complementary flours. The insects included winged termites (Macrotermes subhyalinus), lake-flies (Chaoborus sp.), crickets (Gryllus bimaculatus and Scapsipedus icipe), desert locusts (Schistocerca gregaria), grasshoppers (Ruspolia differens), silkworm pupae (Bombyx mori), wild silk moth caterpillars (Anaphe panda), mopane worms (Gynanisa maja and Gonimbrasia belina), Bunaea alcinoe, and Gonimbrasia zambesina. Fungal isolation comprised 1,080 inoculated culture observations across three independent batches per material type, from which 798 fungal isolates were recovered and identified by culture, microscopy, and internal transcribed spacer (ITS) sequencing.

The results paint a striking picture of fungal prevalence. Aspergillus accounted for 70.7 percent of isolates recovered from insect products, followed by Penicillium at 18.6 percent and Fusarium at 7.4 percent. Penicillium was detected in all 11 insect products, while Fusarium appeared in eight of them. Across all material categories, Aspergillus dominated at 55.3 percent of the 798 recovered isolates, followed by Penicillium at 26.1 percent and Fusarium at 14.5 percent. The distribution of fungal genera differed significantly between material types, with Aspergillus predominating in insects, ingredients, and enriched formulations, while Penicillium was more common in commercial complementary flours.

Beyond mere presence, the researchers probed the toxigenic potential of the recovered fungi using endpoint PCR. Among 44 Aspergillus flavus-like morphotypes, the aflatoxin-biosynthesis genes aflD and aflQ were detected in 32 and 23 isolates, respectively. Among 22 Fusarium-like isolates, the fumonisin-biosynthesis gene FUM1 was detected in 19, and the VERTF intergenic-spacer profile associated with potentially fumonisin-producing Fusarium verticillioides strains appeared in 10. The authors are careful to note that marker detection does not establish gene expression or actual mycotoxin production—but it does provide biological context for the chemical findings that followed.

Using liquid chromatography–tandem mass spectrometry (LC–MS/MS), the team screened 23 mycotoxins in five complementary-food formulations—four insect-fortified and one non-insect control—over three months of storage at approximately 22 degrees Celsius. Six mycotoxins were confirmed: 3-acetyldeoxynivalenol, aflatoxin G1, sterigmatocystin, and fumonisins B1, B2, and B3. Only aflatoxin G1 and fumonisin B1 were quantified above their limits of quantification, at 4.20 µg/kg and 20.31–86.88 µg/kg, respectively. Quantifiable fumonisin B1 occurred more frequently at later storage points and peaked after three months, although the temporal pattern was not uniformly monotonic across formulations. The aflatoxin G1 point estimate fell below the Kenyan total-aflatoxin maximum for processed cereal-based foods for older infants and young children, and the European Union maize-based infant-food fumonisin value was used only as a contextual benchmark, since the formulations were grain-amaranth-based and contained no maize. Neither comparison established compliance or safety.

Notably, fumonisin B1 was detected in all five formulations, including the non-insect control, while the aflatoxin G1 and fumonisin B3 detections occurred only in the control formulation. The findings therefore do not support attribution of the detected mycotoxins specifically to the insect ingredients. Grain amaranth, common to all formulations, may have contributed to the widespread fumonisin occurrence, but the source cannot be assigned because individual ingredient batches were not analyzed separately for mycotoxins. This nuance underscores a broader challenge in multi-ingredient foods: contamination can flow from any component, and pinpointing origins requires ingredient-level surveillance.

The histamine and allergen-related findings add another layer of complexity. Histamine, which forms through microbial decarboxylation of histidine during inadequate handling or storage, is heat-stable and has caused poisoning outbreaks following insect consumption in Thailand. In this study, quantifiable histamine concentrations in 17 insect preparations ranged from 3,108 to 30,232 µg/kg, with the highest values recorded in raw and pan-fried lake flies (Chaoborus spp.). One oven-dried mopane worm preparation (Gonimbrasia belina) exceeded the assay’s upper quantitative limit and was reported as greater than 40,000 µg/kg. Three preparations fell below the assay’s lower limit of quantification. These values are descriptive rather than evidence of regulatory compliance, since no histamine limits currently exist for edible insects or insect-based complementary foods.

On the allergen front, lysozyme-reactive ELISA signals were below 25 µg/kg in all 17 insect preparations, suggesting minimal reactivity with hen’s-egg lysozyme antibodies. However, crustacean-reactive signals exceeded the assay’s upper quantification limit of 400 µg/kg in 16 of 17 preparations, with the remaining oven-dried Gonimbrasia belina result at 382 µg/kg. These signals represent analytical boundaries rather than health-based safety thresholds, and the reacting proteins were not identified. Tropomyosin and arginine kinase are among the arthropod proteins most frequently implicated in cross-reactivity between crustaceans and insects, and previous studies have demonstrated IgE recognition of cricket and grasshopper proteins by shrimp-allergic patients. The authors stress that the ELISA component was exploratory and that confirmation using multiple independently collected batches within each species and processing category is required before clinical conclusions can be drawn.

The study’s conclusions are clear: edible insects remain a promising, sustainable, and nutrient-rich food source, but their safety depends on species, rearing, processing, and storage. The findings support improved hygienic processing, ingredient control, routine fungal and mycotoxin surveillance, prompt post-harvest temperature control, and continued assessment of allergen-related cross-reactivity—particularly when insects are intended for incorporation into complementary foods for infants and young children. As insect-based nutrition scales up across Africa and beyond, this research provides a critical technical foundation for building safe, trustworthy value chains that can deliver on the promise of insects as food without compromising the health of the most vulnerable consumers.

Subject of Research: Fungal contamination, mycotoxins, histamine, and allergen-related immunoreactivity in edible insects and insect-fortified complementary foods

Article Title: Fungal contamination, mycotoxins, histamine, and allergen-related immunoreactivity in edible insects and insect-fortified complementary foods

Article References: Fungal contamination, mycotoxins, histamine, and allergen-related immunoreactivity in edible insects and insect-fortified complementary foods. (n.d.). https://doi.org/10.3389/ffunb.2026.1798430

Image Credits: AI Generated

DOI: 10.3389/ffunb.2026.1798430

Keywords: edible insects, fungal contamination, mycotoxins, histamine, allergen cross-reactivity, complementary foods, food safety, Aspergillus, Fusarium, infant nutrition, Fungal, contamination

The timing is not accidental. Conventional edible lipids face mounting constraints: unsaturated plant oils often lack the solid-fat functionality demanded by bakery fats and spreads, animal fats carry saturated fatty acids and cholesterol, and fish oil, the main source of long-chain omega-3 fatty acids, is both oxidation-prone and increasingly scarce, with global output falling by roughly 21 percent in 2023 according to the FAO. Meanwhile, insects are already being processed at scale into protein concentrates and defatted meals, leaving behind an oil-rich stream that is frequently underused. Recovering that fraction could yield an additional ingredient while preserving a protein-rich co-product for further valorization.

What makes insect oils genuinely interesting, the review contends, is not their fatty-acid composition alone but their triacylglycerol architecture, the specific way fatty acids are assembled onto the glycerol backbone. Three recurring compositional archetypes emerge from the literature. Black soldier fly larvae oil is lauric-rich, containing roughly 28 to 62 percent lauric acid depending on diet and processing, placing it closer to coconut and palm-kernel fats than to typical animal fats. Mealworm, cricket, and locust oils are dominated by oleic and linoleic acids, resembling liquid vegetable oils. Silkworm pupal oil stands apart as an alpha-linolenic-acid-rich oil, with the omega-3 fatty acid accounting for roughly 35 to 38 percent of total fatty acids in representative samples, a profile more comparable to flaxseed or perilla oil than to fish oil, since it delivers ALA rather than the longer-chain EPA and DHA.

These labels, the authors stress, are descriptive rather than a formal classification system, because composition shifts with species, developmental stage, rearing substrate, and extraction method. Diet is the most accessible pre-harvest lever: rye bran raised the lipid content of yellow mealworm larvae to about 30 percent, while rapeseed oil cake reduced it to around 15 percent. Yet the final oil never simply mirrors the feed, because insect digestion, selective deposition, and de novo fatty-acid synthesis impose species-specific limits. Enriching feed with polyunsaturated fats can improve the target profile while simultaneously raising oxidation susceptibility, a trade-off that feed designers must manage as an integrated system.

The review’s central technical argument is that fatty-acid surveys alone cannot predict how an insect oil will behave in food. Intact triacylglycerol species, their positional distribution, and minor constituents such as tocopherols, sterols, and phospholipids jointly determine crystallization, melting, interfacial behavior, and digestion. Cold-pressed black soldier fly larvae oil, for example, contains trilaurin, dilauroyl-myristoyl, and lauroyl-dimyristoyl triacylglycerols as major species, producing a thermal profile similar to palm-kernel and coconut fats. Yet processing can overturn expectations: larvae killed by freezing, freeze-dried, and defatted with supercritical carbon dioxide yielded an oil with a melting peak at 14.51 degrees Celsius and less than 10 percent solid fat at room temperature, while seven other combinations of killing, drying, and extraction retained more than 40 percent solid fat. Species identity and fatty-acid composition, in other words, do not constitute a thermal specification.

Quality attributes are equally process-dependent. Acid values reported across studies range from about 1.1 to more than 97 milligrams of potassium hydroxide per gram, reflecting hydrolytic damage that can continue after insect killing unless lipases are inactivated; blanching suppressed post-mortem lipolysis in black soldier fly larvae more effectively than freezing. Oxidation requires paired primary and secondary indices, because oils with moderate peroxide values can already carry high loads of aldehydic breakdown products. Sensory quality presents its own challenge: crude insect oils may carry grassy, fermented, or rancid notes from pyrazines, alcohols, and oxidation-derived aldehydes, but deodorization, while effective, risks stripping tocopherols and generating refining-related contaminants such as trans fatty acids and glycidyl esters if conditions are too severe.

On the application side, direct incorporation into foods currently has the strongest evidence. In a consumer study of 344 participants, replacing 25 percent of butter with black soldier fly larvae fat in cakes, cookies, and waffles did not reduce overall liking, and waffles maintained acceptance even at 50 percent replacement. Deodorized yellow mealworm oil replaced 50 to 100 percent of vegetable oil in crackers and hummus without lowering liking among 253 consumers, and among 90 tasters, potato chips fried in a 50:50 blend of vegetable and deodorized mealworm oil were the most frequently preferred. Roasted insect oils have even been incorporated into bone broth, shifting the fatty-acid profile toward that of beef while modifying meat-like aromas. More experimental routes, including wax-based oleogels that convert liquid mealworm oil into a shortening-like solid, whey-protein-coated emulsions that enhance lipolysis of silkworm oil, and enzymatic restructuring that repositions fatty acids on the glycerol backbone, remain largely at the prototype or in-vitro stage.

Biological evidence, the review cautions, is overwhelmingly preclinical and material-specific. Silkworm pupal oil showed higher apparent free-fatty-acid release during simulated digestion than linseed oil, and enzymatically restructured versions released even more, but such endpoints do not establish superior absorption or bioavailability in humans. Animal studies have reported reduced hepatic triglycerides in obese Zucker rats fed black soldier fly larvae fat compared with palm oil, altered lipid-metabolism gene expression in fish, and antioxidant and anti-inflammatory signals in cell and worm models, yet none of these findings can be generalized across insect oils as a category. Human trials using chemically characterized, food-grade oils and realistic intake conditions remain absent.

The path to industrial translation runs through several bottlenecks the review enumerates candidly. Batch variability is substantial, intact triacylglycerol data are scarce for most species, and consumer research has rarely tested purchase intention, price tolerance, or the effect of disclosing insect origin, leaving a gap between blind liking and real purchasing behavior. Residual allergenic proteins, including tropomyosin and arginine kinase that can cross-react with crustacean allergens, cannot be assumed absent from minimally refined oils. Regulatory identity is product-specific: in the European Union, authorization of whole or defatted insects does not automatically cover separately extracted oils, and comparable product-specific assessments apply in the United States and China. A single pilot-scale study processing 5.5 kilograms of mealworms with supercritical carbon dioxide achieved 84 percent defatting with promising life-cycle indicators, but the authors emphasize that such single-route assessments cannot support broad comparisons. Their prescription is a structure-property-application framework: match a reproducible, well-characterized oil to a defined product function, apply modification only where it delivers demonstrable advantage, and validate performance under realistic processing, storage, and sensory conditions before insect oils earn a permanent place on the ingredient shelf.

Subject of Research: Composition, functionality, and food applications of edible insect lipids

Article Title: Insect lipids as novel food ingredients: Linking molecular structure and quality attributes to food applications and industrial translation

Article References: Huang, Y., Kitts, D. D., Dabbour, M., Chen, X., Mintah, B. K., Dai, C., & He, R. (2026). Insect lipids as novel food ingredients: Linking molecular structure and quality attributes to food applications and industrial translation. Food Chemistry: X, 39, Article 104577. https://doi.org/10.1016/j.fochx.2026.104577

Image Credits: AI Generated

DOI: 10.1016/j.fochx.2026.104577

Keywords: insect oil, edible insects, triacylglycerol, black soldier fly, yellow mealworm, silkworm pupal oil, food chemistry, oleogel, oxidative stability, novel food, food processing, sustainable fats

The research, conducted by Rebecca Owusu and Kofi Atiah of the University of Cape Coast in Ghana together with Yacouba Kagambega of the Institut de l’Environnement et de Recherches Agricoles in Burkina Faso, addresses two intertwined problems. The first is agricultural: tomato farming in Ghana is plagued by substantial post-harvest losses, meaning that a large share of the crop that farmers work hard to grow never reaches consumers in usable form. The second is nutritional: micronutrient deficiencies remain a persistent public health concern across the country, particularly among populations whose diets lack diversity. Value-added processing of tomatoes into products such as juice, combined with fortification, has been proposed as a strategy that could tackle both problems at once—soaking up surplus harvest that would otherwise spoil while delivering concentrated nutrients to consumers.

Whether such a strategy can work, however, depends entirely on whether consumers accept the product, and that is where the study makes its contribution. The team employed a discrete choice experiment, a well-established method in agricultural and health economics that asks respondents to choose repeatedly between hypothetical product alternatives described by different combinations of attributes. By varying attributes such as the fortification ingredients, the presence of health claims, and whether the product carries certification, and by observing the trade-offs people make, researchers can statistically recover the implicit value that consumers place on each attribute. The approach transforms a subjective preference into a quantifiable economic measure expressed in Ghanaian cedis, the local currency.

The analytical machinery behind the study was correspondingly sophisticated. The authors estimated mixed logit models in what economists call preference space, an approach that allows each consumer’s tastes to differ from the average and thereby captures preference heterogeneity across the sample. They also estimated generalized multinomial logit models in willingness-to-pay space, a formulation that directly models the monetary value respondents attach to attributes and helps account for the scale of the random components in choice behavior. Estimating models in both spaces is a robustness strategy: if the substantive conclusions hold across specifications, researchers can be more confident that the results reflect genuine preferences rather than artifacts of a particular statistical assumption.

The headline result concerns certification. Consumers were willing to pay an additional 0.521 Ghanaian cedis for a certified product, and health claims on the packaging were also positively associated with consumer valuation. In other words, signals of quality assurance and official oversight made the juice more attractive and more valuable in shoppers’ eyes. This is a meaningful premium in a market where price sensitivity is high, and it underscores a broader principle in food economics: in settings where regulatory enforcement may be uneven and food safety concerns are real, third-party certification functions as a costly-to-fake signal of trustworthiness that consumers reward.

The fortification ingredients told a very different story. All three were associated with negative willingness to pay, meaning that adding them to the juice made consumers value it less. Turkey berry powder, soy milk, and powder derived from palm weevil larvae—the edible insect—each detracted from the product’s appeal. The pattern is notable because these ingredients were presumably selected for their nutritional merit; turkey berries are locally known and soy is a recognized protein source, while insect powder represents an emerging frontier in sustainable protein and micronutrient supply. Yet nutritional logic did not translate into market demand. The authors interpret this as evidence that trust-related attributes matter more for consumer acceptance than product formulation involving unfamiliar ingredients. A consumer who cannot judge whether an unusual ingredient is safe, palatable, or appropriate may simply discount the entire product.

This asymmetry between trust signals and ingredient content has practical consequences for anyone hoping to bring fortified foods to market in Ghana or similar contexts. The study suggests that the pathway to consumer acceptance may run through credibility rather than through the nutritional profile alone. A fortified juice carrying recognized certification and a credible health claim starts with a positive valuation that fortification then erodes; the net effect depends on whether the trust premium can outweigh the ingredient penalty. For product developers, the implication is that unfamiliar ingredients may need to be introduced gradually, paired with strong certification, or framed in ways that connect them to familiar food traditions, rather than simply listed on a label and expected to sell on merit.

The research also carries weight for the sustainable development agenda. The authors explicitly situate their work within the Sustainable Development Goals, particularly SDG 2 on zero hunger, SDG 8 on decent work and economic growth, and SDG 12 on responsible consumption and production. The logic of the connection is straightforward. If nutrition-sensitive food innovations can convert perishable surplus tomatoes into shelf-stable fortified products, farmers capture value that post-harvest losses currently destroy, food processors create employment, and consumers gain access to improved dietary quality. But the entire chain depends on the final link: a consumer willing to buy. Evidence that consumers penalize certain fortification ingredients is therefore not a rejection of the sustainable food systems vision but a map of where the friction lies.

The study was conducted with formal ethical oversight, receiving approval from the University of Cape Coast Institutional Review Board under approval number UCCIRB/CANS/2025/007, and was carried out in accordance with the Declaration of Helsinki. Respondents were informed of the study’s purpose, the confidentiality of their answers, and their right to withdraw at any time, with informed consent obtained before the questionnaire was administered. The authors report no competing interests and note that the research received no external funding. In an unusual touch, the acknowledgements credit a supervised student agribusiness project on consumer preferences for non-dairy ice cream in the Cape Coast Metropolis as the inspiration for the tomato juice study—a reminder that graduate training projects can seed publishable research agendas.

Published open access on 5 October 2026 after being received in April and accepted in late September of the same year, the article arrives as a citable early-release version carrying a permanent DOI. Its broader message resonates well beyond Ghana’s tomato sector. Around the world, food scientists are developing fortification strategies that incorporate novel and sustainable ingredients, from insect-derived proteins to plant-based powders, in the pursuit of diets that are both nutritious and environmentally sound. The Ghanaian evidence adds a cautionary but constructive data point: consumers are not blank slates who will adopt nutritionally superior products on command. They respond to trust, familiarity, and credible signals, and they punish unfamiliarity with their wallets. Designing sustainable food innovations that succeed in the market, the study implies, requires as much attention to the economics of belief as to the biochemistry of nutrition.

Subject of Research: Consumer willingness to pay for fortified tomato juice in Ghana

Article Title: Consumer willingness to pay for fortified tomato juice in Ghana and its relevance for sustainable food systems

Article References: Owusu, R., Kagambega, Y., & Atiah, K. (2026). Consumer willingness to pay for fortified tomato juice in Ghana and its relevance for sustainable food systems. Discover Sustainability. https://doi.org/10.1007/s43621-026-04888-x

Image Credits: AI Generated

DOI: 10.1007/s43621-026-04888-x

Keywords: food fortification, willingness to pay, discrete choice experiment, Ghana, tomato juice, post-harvest losses, sustainable food systems, micronutrient deficiency, edible insects, consumer preferences, SDGs, mixed logit

The review begins with a sober assessment of sustainability claims. Insects such as Tenebrio molitor, Acheta domesticus, Locusta migratoria, Alphitobius diaperinus, Bombyx mori and Hermetia illucens offer high feed conversion efficiency, short growth cycles and lower land requirements than conventional livestock, and many species contain all essential amino acids in nutritionally significant amounts. Yet the authors stress that environmental advantages only materialise when the entire production chain is optimised, including rearing substrate, energy use for temperature control, killing method and drying. Insect proteins should therefore be treated as conditional alternatives whose benefits depend on well-controlled systems rather than assumed by default.

Even measuring how much protein an insect contains turns out to be surprisingly tricky. The conventional nitrogen-to-protein conversion factor of 6.25 can overestimate protein content because insect biomass contains nitrogen from chitin and other non-protein compounds. Janssen and colleagues proposed a lower factor of approximately 4.76 for mealworm, lesser mealworm and black soldier fly larvae. Reported values also depend on whether composition is expressed on a fresh-weight or dry-matter basis, and on the developmental stage, rearing diet and processing history of the material. Digestibility adds another layer: in vitro studies show mealworm and cricket proteins can achieve digestibility figures of 79 to 99 percent and favourable DIAAS scores, but these outcomes shift with heat treatment, defatting and chitin reduction, making digestibility a processing-dependent property rather than a fixed species trait.

Processing is where the review’s central framework comes into play. Pretreatments such as killing, blanching, drying, grinding and defatting establish the initial state of the biomass, and each involves trade-offs. Blanching improves microbial and enzyme control but can unfold proteins and promote aggregation that reduces extraction efficiency. Freeze-drying limits thermal damage but is costly, while microwave and hot-air drying scale better yet risk Maillard reactions, lipid oxidation and protein denaturation. Defatting enriches protein and limits oxidation, since residual lipids rich in polyunsaturated fatty acids generate rancid aldehydes such as hexanal and nonanal, but solvent contact and duration can alter protein conformation and downstream recovery. Quantitatively, defatting raised Tenebrio molitor flour from 57.8 to 64.6 percent protein while cutting fat to 2.8 percent, and lifted Hermetia illucens flour from 34.7 to 44.9 percent protein.

Protein recovery routes then diverge sharply. Dry fractionation by milling and sieving is simple and low in water and chemical use, but yields fractions still loaded with lipids, chitin, ash and pigments, making them better suited to bakery and snack applications than to refined functional roles. Alkaline solubilisation followed by isoelectric precipitation boosts purity and yield, but extreme pH can trigger denaturation, browning and unwanted structural changes. Assisted technologies offer further options: ultrasound cavitation disrupts tissues and aggregates, improving extraction yields by 35 to 94 percent in sonicated silkworm pupae, while high-pressure processing increased protein solubility in Protaetia brevitarsis seulensis up to an optimum of 200 megapascals before the benefit declined. No single technology wins outright; the authors insist processing should be designed backwards from the target food.

Post-recovery modification tailors proteins to specific functions, and here the quantitative evidence is striking. Enzymatic hydrolysis of migratory locust protein raised solubility from as low as 10 percent to 55 percent and foamability to 326 percent at pH 3. Cricket hydrolysates reached emulsifying activity indices of up to 32 square metres per gram, compared with 6.23 for defatted cricket flour. But hydrolysis illustrates what the authors call the protein-functional modification dilemma: excessive cleavage weakens interfacial films, releases bitter hydrophobic peptides and, crucially, does not reliably eliminate allergenic epitopes unless proteolysis is extensive, on the order of 60 to 85 percent degree of hydrolysis needed to disrupt major allergens such as tropomyosin. Fermentation offers another route, with fungal fermentation of cricket powder increasing solubility by roughly 20 percent and water-holding capacity from 2.17 to about 2.62 grams per gram, though it demands careful microbiological control.

Application studies show that ingredient form must match product structure. Bread is highly sensitive because insect flour dilutes the gluten network that traps fermentation gases, producing compact crumbs and darker colour, so insects work best as supplementary ingredients. Biscuits, crackers, muffins and protein bars tolerate higher inclusion levels because their quality depends less on gas retention. Extruded snacks sit in between: cricket powder at 12.5 to 15 percent could qualify products as protein sources, but 7.5 percent was recommended to preserve expansion and texture. In meat analogues, insect proteins perform best as complementary fractions within hybrid systems. High-moisture extrusion of insect and soy protein concentrates showed that around 15 to 40 percent insect protein could match the cutting properties of a soy control, while substituting 10 percent of soy protein isolate with cricket powder actually enhanced fibrous anisotropy, although higher levels produced brittle, incoherent extrudates. Three-dimensional printing studies found that pellet fractions of cricket and mealworm at 15 percent gave the best shape fidelity and post-print texture, underlining that fractionation, not the insect species alone, is the controlling design variable.

Liquid foods impose the strictest demands. Beverages require high solubility at acidic pH to avoid sedimentation and cloudiness, making whole insect flours largely unsuitable and pushing formulators toward soluble concentrates and hydrolysates. Consumer testing of mealworm protein shakes identified a rejection threshold of 14.6 percent mealworm content only among blind-tasting participants; health- and sustainability-framed groups showed no comparable threshold, suggesting communication can shift tolerance, though it cannot rescue poor sensory quality. Bioactive peptides add another dimension: cricket hydrolysates produced by microwave-assisted enzymatic hydrolysis showed ACE-inhibitory IC50 values of 0.096 milligrams per millilitre and DPP-IV-inhibitory values of 0.27, better than conventional hydrolysis. The authors caution, however, that these results come from chemical and in vitro enzyme assays and cannot be equated with proven antihypertensive or glycaemic effects in humans.

Safety and regulation complete the picture. Insect biomass can carry Enterobacteriaceae, Salmonella, Listeria, Staphylococcus aureus and spore-forming bacteria, so hurdle-based strategies combining blanching, drying, water-activity control and hygienic handling are essential. Chemical hazards such as mycotoxins and heavy metals depend on rearing substrate, meaning circular production using food-industry side streams requires rigorous contaminant monitoring. Allergenicity remains a critical concern because insects share conserved pan-allergens, including tropomyosin and arginine kinase, with crustaceans, molluscs and house dust mites; one observational study found 73 percent of crustacean- and mite-sensitised patients showed IgE reactivity to recombinant black soldier fly tropomyosin. In the European Union, novel food authorisations are species- and process-specific, as illustrated by the approved partially defatted house cricket powder, which carries mandatory allergen labelling. The review’s conclusion is clear: no single insect ingredient will suit every product. Commercial success will depend on standardised, application-specific ingredients whose processing history, functional performance, safety profile and sensory character are validated together, from raw material to finished food.

Subject of Research: Processing-structure-function relationships in edible insect proteins for food applications

Article Title: Designing edible insect proteins for food applications: Processing-Structure-Function relationships, product performance and safety trade-offs

Article References: Nguyen, C. H., & Truong, D. H. (2026). Designing edible insect proteins for food applications: Processing-Structure-Function relationships, product performance and safety trade-offs. Journal of Agriculture and Food Research, 31, Article 103340. https://doi.org/10.1016/j.jafr.2026.103340

Image Credits: AI Generated

DOI: 10.1016/j.jafr.2026.103340

Keywords: edible insects, insect protein, food processing, protein functionality, allergenicity, food safety, meat analogues, protein hydrolysates, novel foods, sustainable protein, techno-functional properties, consumer acceptance

The research team obtained third-instar larvae from a single commercial rearing batch at a farm in Kumasi, where the insects were raised on oil palm frond substrate under controlled conditions. The larvae, averaging just over eight grams each, were freeze-killed and then divided into four treatment groups: fresh and washed, boiled, fried, and roasted. This allowed the investigators to compare how each common culinary preparation affected the proximate composition, mineral content, heavy metal burden, and microbiological quality of the final product. All proximate and mineral analyses were performed in triplicate on homogenized composites of roughly twenty larvae each, while microbiological testing was conducted in duplicate, with one-way analysis of variance and Tukey’s post hoc tests used to identify statistically significant differences among treatments.

The nutritional results highlight how dramatically cooking method reshapes the food value of these larvae. Fresh palm weevil larvae contained about 71 percent moisture and roughly 11.8 percent protein. Frying drove moisture down to 30.5 percent and concentrated the protein to 27.5 percent, an increase of more than 133 percent relative to the raw material, while roasting lifted protein to 25.3 percent. Boiling, by contrast, slightly increased moisture and actually reduced protein to 10.7 percent, likely because water-soluble nitrogenous compounds leached into the cooking water. Fat told a different story: frying more than doubled the fat content to 34.4 percent as the larvae absorbed cooking oil, pushing the energy value of the fried sample to 442 kilocalories per 100 grams, compared with 182 for the fresh larvae and only 173 for the boiled ones.

Mineral analysis revealed that calcium and iron were the dominant essential minerals in all samples, and both increased significantly with dry-heat cooking. Calcium rose from about 82 parts per million in fresh larvae to 143 ppm in fried and 121 ppm in roasted samples, while iron climbed from 24 ppm to 52 and 45 ppm respectively. Manganese and copper followed the same pattern. Zinc behaved differently, with fresh and boiled samples retaining more of this trace element than the fried and roasted ones, suggesting that moisture loss during high-temperature cooking can carry some dissolved minerals out of the tissue. The authors attribute the overall mineral profile partly to the feed substrate on which the larvae were reared, and they note that such profiles vary widely with geography, diet, and larval life stage.

The chemical safety findings are where the study turns cautionary. Mercury and arsenic were not detected above the analytical method’s limits, but those limits, 0.175 milligrams per kilogram for mercury and 0.425 for arsenic, actually exceed the Codex Alimentarius maximum tolerable limits of 0.02 and 0.01 milligrams per kilogram respectively. In other words, the method could not demonstrate compliance with international thresholds for these two metals, an uncertainty the researchers flag explicitly. More concretely, lead concentrations in all samples ranged from 0.33 to 0.39 milligrams per kilogram, slightly exceeding the Codex limit of 0.30, and cadmium ranged from 0.82 to 0.94 milligrams per kilogram, far above the tolerable limit of 0.05. Cadmium, classified by the International Agency for Research on Cancer as a Group 1 human carcinogen, is associated with kidney damage and bone demineralization under chronic exposure.

To translate these concentrations into health risk, the team applied standard United States Environmental Protection Agency frameworks, assuming a daily intake of 50 grams of larvae and a 70-kilogram adult body weight. Target hazard quotients for all four metals came in below 1.0, the threshold for acceptable non-carcinogenic risk, though values for cadmium and arsenic hovered near or above 0.5, close enough that the authors urge preemptive measures before they potentially cross the line. For lead, which has no established safe threshold for neurodevelopmental effects, the margin of exposure calculated against the European Food Safety Authority benchmark ranged from 1.79 to 1.96, far below the value of 10 generally considered indicative of low concern. For cadmium, incremental lifetime cancer risk estimates of 3.4 to 4.1 times ten to the minus six exceeded the EPA’s acceptable level of one times ten to the minus six, though they remained below the high-risk threshold. A sensitivity analysis showed that at intakes of 10 grams per day all hazard quotients stayed comfortably low, but at 30 grams per day or more, cadmium risk climbed appreciably for fried and roasted portions.

Microbiological testing added another layer of nuance. Raw, unwashed larvae carried aerobic mesophile counts of 7.0 log colony-forming units per gram, well above the European Union limit of 5 log for ready-to-eat foods, along with substantial loads of yeasts, molds, and Enterobacteriaceae. Simply rinsing the larvae under running water reduced aerobic counts and Enterobacteriaceae by roughly two log cycles. Boiling, frying, and roasting then cut aerobic counts to between 1.5 and 3.0 log, within acceptable limits for cooked products, and eliminated detectable yeasts, molds, and Enterobacteriaceae entirely. Crucially, Staphylococcus aureus and Clostridium perfringens were not detected in any sample, meeting both Codex and EU criteria. The message is clear: raw Akokono, as currently produced, is not microbiologically fit for direct consumption, but thorough cooking renders it safe on these indicators.

The researchers also employed ultraviolet-visible spectroscopy as a fingerprinting tool, scanning pulverized samples between 200 and 400 nanometers. Fresh and boiled larvae, with their high moisture, showed indistinct absorption peaks below 300 nanometers, consistent with peptide bonds and saturated fatty acids. Fried and roasted samples produced distinctive peaks at longer wavelengths, between 300 and 375 nanometers, which the authors interpret as evidence of altered protein structure and, in the fried sample, possible lipid oxidation and Maillard reaction products from protein-sugar interactions. The fried sample alone displayed a standalone peak at 350 nanometers. While largely confirmatory, the spectral data illustrate how each cooking method leaves a unique chemical signature on the larvae and reinforce the conclusion that these insects are complex matrices of proteins, lipids, and secondary metabolites.

Water activity measurements rounded out the physicochemical picture, ranging from 0.72 in roasted samples to 0.77 in boiled ones. Interestingly, although fried larvae had lower moisture content than roasted ones, their water activity values were statistically indistinguishable, underscoring that moisture content and water availability do not scale linearly. Both fried and roasted products, with water activity near 0.72 to 0.73, would be expected to resist microbial growth similarly during storage, a relevant consideration for shelf life as commercial Akokono production scales up.

The authors are careful to frame their conclusions within the limits of their design: all samples came from a single commercial batch at one Kumasi farm, and the nutritional and contaminant profiles of R. phoenicis are known to vary with rearing substrate, season, geography, and developmental stage. Generalizing these results to wild-harvested larvae or other farms would be premature, and the team calls for future studies spanning multiple batches, farms, and seasons to establish representative reference values. Still, the study delivers an actionable picture for Ghanaian policymakers and food safety authorities. Farmed palm weevil larvae are undeniably nutritious, offering protein levels that rival conventional meats when dry-cooked, along with meaningful calcium and iron. But the lead and cadmium findings, the lead margin of exposure in particular, and the high microbial loads in raw product signal that standards, hygienic processing protocols, and routine contaminant monitoring must accompany any push to mainstream Akokono as a food of the future. Cooking, the data show, is not optional; it is the difference between a hazardous raw grub and a safe, protein-rich plate.

Subject of Research: Nutritional composition, heavy metal contamination, and microbiological safety of farmed palm weevil larvae (Rhynchophorus phoenicis) prepared by different cooking methods in Ghana

Article Title: Nutritional Composition, Chemical Safety, and Microbiological Quality of Farmed Palm Weevil Larvae (Rhynchophorus phoenicis) From a Commercial Rearing Unit in Ghana

Article References: Mintah, B. K., Ketemepi, H. K., Asiamah, E., Agyekum, A. A., Blessie, E. J. S., Arthur, A. B., & Dabbour, M. (2026). Nutritional Composition, Chemical Safety, and Microbiological Quality of Farmed Palm Weevil Larvae ( Rhynchophorus phoenicis ) From a Commercial Rearing Unit in Ghana. Food Science & Nutrition, 14(10), Article e72402. https://doi.org/10.1002/fsn3.72402

Image Credits: AI Generated

DOI: 10.1002/fsn3.72402

Keywords: edible insects, palm weevil larvae, Akokono, food safety, heavy metals, cadmium, lead, entomophagy, Ghana, food processing, microbiology, sustainable protein

The research, published in Food Science and Biotechnology, was led by Yu Bin Yang, Hyun Jun Seok, and corresponding author Sung Ho Lee of the Department of Food Science and Technology. The team set out to map how volatile organic compounds, or VOCs, in mealworm protein hydrolysates change across a multi-stage processing pipeline that includes enzymatic hydrolysis, lactic acid fermentation, and spray drying based on an alkali-solubilization and precipitation approach. Rather than treating flavor as an afterthought to be masked with seasonings, the researchers treated it as a chemical system that could be deliberately engineered, tracking individual odor-active molecules at each stage of production.

The starting material was raw mealworm powder, and the analytical baseline established from it is telling. The unprocessed powder contained representative off-flavor-related VOCs, most notably hexanal, hexanoic acid, and a cluster of esters associated with raw material character. Hexanal is a classic secondary product of lipid oxidation and is responsible for the green, grassy, cut-plant smell that many consumers associate with damaged seed oils and beany legume products. Hexanoic acid contributes rancid, sweaty, cheese-like notes at even modest concentrations, and raw-material esters add fruity but unripe, solvent-like nuances. Together, this trio of chemical signatures forms much of the sensory barrier that has kept insect protein out of mainstream food formulations despite its impressive nutritional credentials.

To break down mealworm protein and, in the process, disrupt the chemical environment that produces these off-flavors, the researchers compared two sequential enzymatic hydrolysis systems. The first paired Alcalase, a robust alkaline serine protease widely used in industrial protein processing, with Flavourzyme, a fungal enzyme complex that contains both endopeptidase and exopeptidase activities and is often deployed to generate savory, umami-rich hydrolysates. The second system paired Alcalase with Protana Prime, a commercial protease preparation optimized for debittering and flavor applications in protein ingredients. By running two enzyme combinations in parallel, the team could separate the general effects of hydrolysis from the specific effects of enzyme choice, a comparison that proved consequential for downstream flavor chemistry.

After hydrolysis, the protein solutions underwent lactic acid fermentation, a biotechnological strategy with a strong track record in plant protein de-flavoring. Lactic acid bacteria metabolize small carbonyl compounds and acids, and previous work on soymilk and plant-based meat analogues has shown that fermentation can reduce beany aldehydes such as hexanal substantially. In the mealworm system, the results followed the same logic: the off-flavor-related compounds that dominated the raw powder were markedly reduced after hydrolysis and fermentation, with several falling below the detection threshold of the analytical method. This is a critical outcome, because it means the offending molecules are not simply diluted but effectively removed from the volatile profile, a chemically cleaner result than masking with spices or sweeteners could ever achieve.

The two enzyme systems also differed in a way that shaped everything that followed. The hydrolysate produced by the Alcalase-Protana Prime system, designated AP-H, contained higher levels of free amino acids than the Alcalase-Flavourzyme hydrolysate, AF-H. Free amino acids matter enormously in flavor generation because they serve as precursors for volatile formation during subsequent thermal processing. In particular, amino acids participate in the Maillard reaction and in Strecker degradation, pathways that generate pyrazines, aldehydes, and other compounds responsible for roasted, nutty, and cocoa-like aromas. A hydrolysate rich in free amino acids is therefore a richer chemical feedstock for aroma development when the material is heated or dried, effectively stocking the pantry from which desirable smells are later cooked up.

The final stage of the pipeline combined fermentation with spray drying, an industrial technique in which a liquid feed is atomized into hot air to yield a dry powder. Spray drying is prized for shelf stability and convenience, but its thermal component is not flavor-neutral: it drives chemical reactions among amino acids, peptides, and reducing compounds present in the feed. The stand-out sample in the study, AP-HF-SD, which had undergone the Alcalase-Protana Prime hydrolysis, fermentation, and spray drying, was characterized by high levels of 2,3-butanediol, increased benzaldehyde, and the appearance of pyrazines. 2,3-Butanediol is a fermentation-associated compound with a mild, slightly sweet character, while benzaldehyde contributes a familiar almond-like note that is generally regarded as pleasant in processed foods. Pyrazines are among the most valued aroma molecules in the food industry, underpinning the roasted, baked, and nutty scents of coffee, bread crust, and grilled meat.

Together, this pattern of volatile change points to a processing-associated modulation of flavor: the harsh green and rancid notes of the raw material were dismantled, and in their place emerged compounds that consumers typically associate with savory, roasted, or baked foods. The authors themselves are appropriately measured on this point. The study reports chemical profiles rather than human taste-test verdicts, and the paper explicitly notes that sensory evaluation and odor activity analysis, which weigh compound concentrations against their odor thresholds to estimate real perceptual impact, are still required to confirm that the chemical improvements translate into a perceived flavor benefit. Concentration data alone cannot guarantee that a volatile is smelled, since some compounds dominate a profile while contributing little at levels below their thresholds.

Even with that caveat, the implications for the alternative protein industry are significant. Consumer acceptance remains the single largest obstacle to insect protein entering mainstream diets in Europe, North America, and much of Asia, and sensory attributes consistently rank among the top reasons cited for rejection. A processing route that uses food-grade enzymes, generally recognized lactic acid bacteria fermentation, and standard spray drying equipment is compatible with existing industrial infrastructure, meaning manufacturers would not need to invent novel unit operations to adopt it. The finding that enzyme selection propagates all the way through to the final volatile profile also gives formulators a practical lever: choosing a protease system that liberates more free amino acids appears to set up the product for richer aroma generation during drying.

The broader context is a rapidly growing body of work on insect protein as a climate-friendly alternative to livestock. Mealworms convert feed to edible protein with high efficiency, emit comparatively few greenhouse gases, and can even be raised on agricultural by-products. As regulatory approvals for insect-derived foods expand, the technical challenge shifts from production to palatability, and studies like this one demonstrate that flavor is not an immovable property of an ingredient but a designable feature of the process. If follow-up sensory panels confirm that hydrolyzed, fermented, and spray-dried mealworm protein genuinely smells and tastes better, the combination could become a standard pretreatment in insect protein ingredient manufacturing, helping to move mealworms from novelty snack territory into protein bars, meat analogues, savory seasonings, and everyday processed foods.

Subject of Research: Improving flavor quality of mealworm (Tenebrio molitor) protein hydrolysates through integrated enzymatic hydrolysis, lactic acid fermentation, and spray drying

Article Title: Integrated enzymatic hydrolysis and lactic acid fermentation improve off-flavor removal and aroma generation in mealworm (Tenebrio molitor) protein hydrolysates

Article References: Integrated enzymatic hydrolysis and lactic acid fermentation improve off-flavor removal and aroma generation in mealworm (Tenebrio molitor) protein hydrolysates. (n.d.). https://doi.org/10.1007/s10068-026-02300-y

Image Credits: AI Generated

DOI: 10.1007/s10068-026-02300-y

Keywords: mealworm, Tenebrio molitor, edible insects, enzymatic hydrolysis, lactic acid fermentation, volatile organic compounds, off-flavor removal, aroma generation, protein hydrolysates, spray drying, food science, alternative protein