Imbrasia Belina Research Articles

Edible caterpillars (Gonimbrasia belina and Gynanisa maja) as emerging source of nutrients and bioactive compounds

Globally, despite the commercial and cultural importance of edible caterpillars (Gynanisa maja and Gonimbrasia belina), comprehensive information on their dietary and therapeutic benefits has not been fully explored. The study was aimed at evaluating the nutritional composition and bioactive compounds profile of two important edible caterpillars (Gonimbrasia belina and Gynanisa maja) in Africa. Our results demonstrated that G. belina and G. maja are capable of amplifying host plant protein (17 %) by 4.3-folds [72.8 %] and 3.6-folds [61.3 %], respectively. Lysine (32.6 mg/g), methionine (12.5–27.1 mg/g) and valine (7.7–25.4 mg/g) value were significantly harnessed. Substantial amounts of ω−3 fatty acids (methyl 5Z,8Z,11Z,14Z,17Z-eicosapentaenoate and methyl 9Z,12Z,15Z-octadecatrienoate), minerals [iron (3.6–21.2 mg/100 g), zinc (7.1–17.3 mg/100 g), calcium (55.1–60.4 mg/100 g)] and vitamins [retinol (0.02–0.03 mg/kg), γ tocopherol (0.05–0.07 mg/kg) and α-tocopherol (1.2 mg/kg)] were detected. Important phytochemical [flavonoids: rutin (7.8–20.4 ng/g), quercetin (7.2–9.0 ng/g), luteolin (7.4–7.5 ng/g), apigenin (20.8–28.6 ng/g) and kaempferol (3.3–6.5 ng/g)] and phytosterols [stigmasta-3,5-diene, campesterol and sitosterol] were identified. These findings suggests that both edible caterpillars contain sufficient nutrients and therapeutic compounds, which when integrated into human food products, either whole, in-part, or processed will greatly contribute towards countering nutritional insecurity and improve livelihoods of people in many countries.

Influence of soil properties on pre-pupal burrowing, pupation and nutritional content of Gonimbrasia belina Westwood

Influence of soil properties on pre-pupal burrowing, pupation and nutritional content of Gonimbrasia belina Westwood

Effect of fermentation, malting and ultrasonication on sorghum, mopane worm and Moringa oleifera: improvement in their nutritional, techno-functional and health promoting properties.

Food processing offers various benefits that contribute to food nutrition, food security and convenience. This study investigated the effect of three different processes (fermentation, malting and ultrasonication) on the nutritional, techno-functional and health-promoting properties of sorghum, mopane worm and Moringa oleifera. The fermented and malted flours were prepared at 35°C for 48 h, and for ultrasonication, samples were subjected to 10 min at 4°C with amplitudes of 40-70 Hz. The biochemical, nutritional quality and techno-functional properties of the obtained flours were analysed using standard procedures. Fermentation resulted in significantly lower pH and higher titratable acidity in sorghum and mopane worm (4.32 and 4.76; 0.24 and 0.69% lactic acid, respectively), and malting resulted in higher total phenolic content and total flavonoid content in sorghum (3.23 mg GAE/g and 3.05 mg QE/g). Ultrasonication resulted in higher protein and fibre in raw sorghum flour (13.38 and 4.53%) and mopane worm (56.24 and 11.74%) while raw moringa had the highest protein (30.68%). Biomodification by fermentation in sorghum led to higher water and oil holding capacity and increased dispersibility in the ultrasonicated samples. Ultrasonication of mopane worms led to higher water holding capacity, oil holding capacity and dispersibility. Lightness was found to be significantly higher in the fermented samples in sorghum and mopane worm. Raw moringa had the greatest lightness compared to the ultrasonicated moringa. Moringa had the most redness and browning index among all samples. In this study, all the investigated processes were found to have caused variations in flours' biochemical, nutritional and techno-functional properties. Ultrasonication process was noteworthy to be the most efficient to preserve the nutritional value in sorghum, mopane worm and M. oleifera flours.

Gender differentials in primary processing and market participation by mopane worm harvesters in Zimbabwe: insights from the COVID-19 pandemic phase

BackgroundGender disparities in access to inputs, markets, financial inclusion, and participation in strategic value chains are major developmental challenges in emerging economies. Participation in the edible insect value chain has become an essential source of income, food, and nutrition in some African countries. This paper uses a bivariate probit model to examine the gender differentials for primary mopane worm harvesters’ participation in primary processing and market participation during COVID-19 in Southeastern Zimbabwe. Using a structured questionnaire, the data were gathered from 393 primary harvesters in five purposively selected wards in the Gwanda District of Zimbabwe. This study examines the gender differentials for primary mopane worm harvesters’ participation in primary processing and market participation during COVID-19 in Southeastern Zimbabwe.ResultsResults show that women are likelier to participate in primary value addition to preparing for the lean season opportunities. There are gender differentials in the participation in markets during COVID-19. Results show a significant negative relationship between participants' ages and female engagement in mopane processing and a positive correlation with female involvement in lean COVID-19 season marketing. Male harvesters’ participation in the lean market during the COVID-19 pandemic was significantly correlated positively with age and education level, while the choice to participate in the lean market was negatively correlated with the dependency ratio.ConclusionsCollaborative, community-centric, and gender-accommodative development of the mopane worm value chain is important. Focal issues are on supporting primary value addition for lean season market participation and during market shocks such as COVID-19. This can be a leap towards gender equality and improving livelihoods of women and men in mopane harvesting areas. The study recommends marketing and district-specific policies explicitly addressing mopane worm harvesting and marketing affects market participation and primary value-addition decisions.

Dynamics and socio-environmental impacts of mopane worm harvesting in rural communities in Zimbabwe: prospects for climate-smart approaches

Dynamics and socio-environmental impacts of mopane worm harvesting in rural communities in Zimbabwe: prospects for climate-smart approaches

Promoting Ecosystem Conservation and Food Security through Sustainable Harvesting of Edible Caterpillars in Kanchibiya District, Zambia

Insects play a vital role in enhancing food security and improving the livelihoods of rural communities. This study focused on the identification of caterpillar harvesting practices in Zambia, particularly in Chief Kopa’s village, Kanchibiya District, Muchinga Province, where the caterpillars of Gynisa maja and Gonimbrasia belina play a crucial role in food security. A mixed-methods approach was employed, utilizing face-to-face interviews and self-administered questionnaires to capture both qualitative and quantitative insights. Quantitative data, including caterpillar harvesting amounts and correlations with tree destruction, underwent statistical analyses, including ANOVA and post-hoc Tukey's HSD tests. The Chi-square test explored gender distribution across research sites. Qualitative data from open-ended questions during interviews underwent thematic analysis. The study sampled 100 respondents from six areas, and the results revealed significant differences in caterpillar harvesting amounts among villages. Post-hoc tests identified specific pairwise differences. The findings indicated that traditional harvesting methods persisted, with limited adherence to rules. A significant positive correlation was observed between caterpillar harvesting practices and evolving trends such as increased harvesting intensity, changes in harvesting methods, and environmental impact and tree destruction (p=0.001, r=0.917). The study contributed valuable insights into past caterpillar harvesting practices, proposing conservation strategies for enhanced food security and sustainability. The study proposes a multifaceted approach to balance ecosystem conservation with food security in Kanhaiya District, emphasizing the importance of sustainable caterpillar harvesting. Recommendations include developing community-based sustainable harvesting guidelines, such as rotational zones and harvest limits, alongside education programs to raise ecological awareness. It advocates for diversifying livelihoods and food sources to lessen dependence on caterpillars, ensuring gender-inclusive participation in these initiatives. Monitoring and further research are essential to adapt strategies effectively. These measures aim to preserve the ecosystem, ensuring the caterpillar's role in food security and offering socioeconomic benefits by fostering community resilience and reducing food insecurity vulnerabilities

Host tree-based scenario modelling for predicting a key edible insect, mopane worm Gonimbrasia belina (Westwood, 1894) distribution in Southern Africa

Abstract Gonimbrasia belina, known as the mopane worm, is a large edible caterpillar in tropical and subtropical regions. However, little is known about the bioecology of this species as influenced by its host trees. This study evaluated the importance of different potential host trees in understanding mopane worms’ behaviour and spatial distribution. To assess their relative importance, the study compared models incorporating various mopane worm host trees and predictor variables. Using the species distribution modelling (SDM) package in R, an ensemble of random forest (RF), support vector machine (SVM), and boosted regression tree (BRT) algorithms were used to assess the spatial extent of mopane worm distribution in Southern Africa. Four host tree-based scenarios were developed to assess their contribution to the relative distribution of the mopane worm i.e. (1) by excluding all the potential host trees as explanatory variables and considering only the environmental variables, (2) focusing on the primary host tree, Colophospermum mopane as an explanatory variable together with the other environmental variables, (3) incorporating all the host trees, including C. mopane and (4) examining all other host trees excluding C. mopane. Results demonstrated that incorporating all host trees enhanced the models’ predictive abilities (mean AUC = 0.87) underscoring the significant impact of the alternative host trees on the mopane worm distribution patterns beyond just the C. mopane. This study highlights the significance of host trees in predicting the behaviour and distribution of mopane worm populations, providing valuable insights and decision-making for mopane worm use as an alternative protein source, conservation efforts, and land management practices.

The Biodiversity, Food Security, and Poverty Nexus in the Musina-Makhado Special Economic Zone of South Africa

Wild-sourced foods are entrenched among African women as a survival resource, with the potential to be expanded. Instead of optimising food security, current linear economic growth models in South Africa favour large environment-degrading projects, such as special economic zones and mining, that increase the gap between the wealthy and poor sectors of society. The contentious Chinese-funded Musina–Makhado Special Economic Zone (MMSEZ) planned for the Limpopo province of South Africa is used as a case study in this paper. The MMSEZ case demonstrates the failure of an Environmental Impact Assessment (EIA) to consider alternative land use suited to a biodiverse economy and existing livelihood strategies. Notably, the availability of a popular edible insect, the mopane worm, was not surveyed at a time when it might have been visible. Despite a local and global interest in insect protein, this opportunity was not considered as a means to improve food security and income streams for local unemployed African women.

Development of a nutritious cereal-based instant porridge by the incorporation of protein-rich insect powder – An example from Zimbabwe

Maize in Zimbabwe lacks essential nutrients like protein, iron, and zinc. This study explored alternative ingredients, including climate smart cereals used in porridge, to address this issue. A fortified porridge was developed by adding mopane worm powder, known for its high protein content. Consumer analysis in the UK and Zimbabwe confirmed acceptability of the fortified porridge. The study also assessed the nutritional quality by examining protein, iron, and zinc bioaccessibility after digestion. Results showed a significant increase in the porridge's nutritional profile. A 20 kg child consuming a 50 g portion of the fortified porridge had a potential 230 % increase in protein uptake and 164 % and 109 % increases in iron and zinc uptake, respectively. Acknowledging dietary diversity and use of local raw materials, the study concludes that food-to-food fortification offers a recommended and sustainable solution to address food security challenges in sub-Saharan African nations.

Effects of post-harvesting practices on heavy metal levels of mopane caterpillar (Gonimbrasia belina) products and associated risk assessment

Abstract Mopane caterpillars (Gonimbrasia belina) are one of the most consumed edible insects in Southern Africa, and they contribute nutritional benefits to human health. However, their contribution to the food and nutritional security can be hindered by food safety concerns due to heavy metal contamination associated with harvesting, processing and poor post-harvest practices. This study investigated the effectiveness of post-harvest practices (degutting, charcoal roasting and sun drying, boiling, frying and open pan roasting) in reducing the heavy metal contaminants (cadmium (Cd), mercury (Hg), lead (Pb), nickel (Ni), aluminium (Al), zinc (Zn), copper (Cu) and iron (Fe)) in mopane caterpillar sourced from Gwanda district in Zimbabwe. The post-harvest practice categories used in this study included: unprocessed (ungutted and naturally degutted samples), processed (manually degutted, and charcoal roasted and sun-dried), and cooked (boiled and salted; boiled, salted and roasted, and boiled, salted and fried) samples. An atomic absorption spectrometry (AAS) was used for quantification of metals and the values detected were used to assess health risks to consumers using a quantitative risk assessment calculation method. The unprocessed and manually degutted samples showed higher levels Cd and traces of Pb, while charcoal roasting and sun drying resulted in elevated levels of Al, Zn, Cu and Fe. Hg and Ni were not detected in any of the unprocessed, processed or cooked samples. Cooking processes resulted in reduction of the concentrations of detected metals to levels within the permissible values. The health risk assessment disclosed noncarcinogenic risks based on the high hazard index (HI) values (HI > 1) in unprocessed, processed, boiled and salted, and boiled, salted and roasted samples, indicating that caution should be taken. The overall findings from the study shows that by cooking mopane caterpillars through boiling and frying, health risks associated with heavy metal contamination can be reduced.

Effects of seasonal variation and geographical location on the nutritional composition of mopane worm (Gonimbrasia belina)

Mopane worm (Gonimbrasia belina) consumption contributes to the sustainable supply of protein and several other nutrients for low socio-economic communities. However, mopane worm are bivoltine, producing two generations per rainy season which is postulated to affect their nutritional value. This research investigated the effect of emergence season and geolocation on the nutritional composition of mopane worms. Proximate, mineral composition and fatty acid profile were analysed on degutted mopane worm samples collected over three mopane worm emergence seasons (November-December 2020, April-May 2021, and November-December 2021) from three locations in Gwanda district, Zimbabwe. Crude protein and crude fat ranged between 52.5-58.8 and 12.0-18.6% DM respectively. Potassium (1,195.3-1,759.9), magnesium (104.6-225.5) and calcium (51.2-145.5) were the most abundant macroelements (mg/100 g DM) whilst iron (10.6-21.6) and zinc (13.8-17.9) were the most abundant microelements (mg/100 g DM). Using an attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), mopane worm fat was found to be highly saturated with oleic (ω-9), linoleic (ω-6) and palmitoleic (ω-7) fatty acids. Furthermore, the results revealed a significant (Bonferroni-correction α<0.002) influence of geolocation (sampling location) on mineral content of mopane worms whilst emergence season had a significant influence on fat, protein, ash crude fibre and mineral content. These findings indicate that mopane worm due to their high content of both macro- and micronutrients could contribute significantly to the alleviation of protein, zinc, and iron deficiencies in target communities. More so, the findings on nutritional variation due to emergence season and geolocation provide information that is key in domestication of the mopane worm for realisation of its optimum nutrient content.

Potential decline in the distribution and food provisioning services of the mopane worm (Gonimbrasia belina) in southern Africa.

The mopane worm (Gonimbrasia belina) is an edible insect distributed across southern Africa. As a culturally important source of food, the mopane worm provides nutrition, livelihoods and improves wellbeing for rural communities across its range. However, this is strong evidence that insect populations are declining worldwide, and climate change is likely to cause many insect species to shift in their distributions. For these reasons, we aimed to model how the ecosystem service benefits of the mopane worm are likely to change in the coming decades. We modelled the distribution of the mopane worm under two contrasting climate change scenarios (RCPs 4.5 and 8.5). Moreover, given that the mopane worm shows strong interactions with other species, particularly trees, we incorporated biotic interactions in our models using a Bayesian network. Our models project significant contraction across the species' range, with up to 70% decline in habitat by the 2080s. Botswana and Zimbabwe are predicted to be the most severely impacted countries, with almost all habitat in Botswana and Zimbabwe modelled to be lost by the 2080s. Decline of mopane worm habitat would likely have negative implications for the health of people in rural communities due to loss of an important source of protein as well as household income provided by their harvest. Biogeographic shifts therefore have potential to exacerbate food insecurity, socio-economic inequalities, and gender imbalance (women are the main harvesters), with cascading effects that most negatively impact poor rural communities dependent on natural resources.

The Use of Gonimbrasia belina (Westwood, 1849) and Cirina forda (Westwood, 1849) Caterpillars (Lepidoptera: Sarturniidae) as Food Sources and Income Generators in Africa.

Gonimbrasia belina (mopane worm) and Cirina forda caterpillars (Lepidoptera: Saturniidae) are mostly found in shrubs and trees, from where they are collected as larvae and are widely consumed across southern Africa by rural and increasingly urban populations. These caterpillars are among the most prominent, traded, and economically beneficial edible insects found in Western African countries, but also in South Africa, Zimbabwe, Botswana, and the Democratic Republic of the Congo. Over the years, these caterpillars have evolved from being part of the diet in various communities to playing a vital role in income generation. In addition, consumption of G. belina and C. forda caterpillars as potential food sources has gained momentum due to their potential for contributing to livelihoods and mitigating food security challenges across Africa while providing significant benefits to developing countries on a socio-economic and ecological level. Edible caterpillars serve as a good source of rich nutrients such as proteins, fatty acids, and micronutrients and can be used in formulating nutrient-dense complementary foods. However, limited information is available, specifically on different trees that serve as hosts to these caterpillars, as they depend on the leaves as their only source of food. In addition, the review aims to critique and document knowledge on the nutritional benefits, acceptance of the use of these caterpillars as food security, commercial value, and level of acceptance towards the utilization of caterpillars as food sources.

Effect of selected retail packaging materials, storage temperature and time on the quality of dried mopane worm (Imbrasia belina)

This study assessed the effects of selected retail packaging materials, storage temperature and duration on the quality and shelf life of traditionally processed and sun-dried mopane worms (Imbrasia belina). Changes in the quality of dried mopane worms (MW) were evaluated in a 2 x 2 x 5 factorial experiment comprising packaging materials (low-density polyethylene (LDPE) and high-density polyethylene (HDPE)), storage temperature (ambient and accelerated), and storage time (0, 30, 60, 90 and 120 days) with three replications. Dried MW samples were analysed for changes in physicochemical (ash, moisture, fat, protein content and colour, microbiological (yeast, mould and coliform count), and sensory (colour, taste, texture and overall acceptability) qualities. The results of the experiment were subjected to ANOVA, and the means were separated using the post hoc Tukey test at 5% level of significance. Packaging material did not significantly (p > 0.05) affect ash, moisture, fat, protein content, yeast and coliform count, and sensory qualities of dried MW. However, the mould count and colour parameters of dried MW were significantly (p < 0.05) affected by packaging material. Storage time significantly affected (p < 0.05) moisture, fat, protein content, colour parameters and sensory qualities of dried MW. The ash content was not significantly (p > 0.05) affected by storage time, but the storage temperature significantly affected (p < 0.05) ash, moisture content and colour parameters of dried MW. The three-way interaction between packaging material, storage temperature and time was not significant (p > 0.05) for all proximate composition and microbial quality parameters, indicating that it is safe to consume dried MW over a period of 120 days post-processing. This study recommended that a further study for storage periods greater than 120 days be done to determine the shelf life of traditionally processed dried MW packaged in retail-sized HDPE and LDPE. The HDPE performed better than LDPE in preserving the quality of dried MW, as evidenced by the better-quality parameters recorded under this packaging material. Key words: Mopane worm, retail packaging, shelf life, food quality, storage, temperature, time

Association between consumption of edible insects with dietary diversity, and household food and nutrition security in Southern Zimbabwe

Edible insects are nutritious with potential to improve nutritional outcomes and livelihoods in low-income countries. However, it is not clear whether consumption of edible insects is positively correlated with improved dietary diversity and food security indicators. Therefore, this cross-sectional study was designed to investigate the relationship between consumption of edible insects and diet diversity and food security indicators among children and adults from Gwanda district, Matabeleland province in Southern Zimbabwe. The survey collected data on the following; household sociodemographic characteristics, household dietary diversity score (HDDS), food consumption score (FCS), and child dietary diversity score (CDDS). Logistic regression was used to examine the associations between edible insect consumption and food security indicators. A total of 303 households were surveyed. A high proportion were edible insect consumers (80.9%) and the rest non-consumers (19.1%). The most consumed insect was mopani worms (Gonimbrasia belina, madora, amacimbi) (74.8%). The consumption of mopani worms was highest in the age group 20-49 years (34.4%) and significantly associated with being married and age of the household head. There was no difference between the mean CDDS for consumers (5.9±1.7) and for non-consumers (6.0±2.0) (p=0.802). The median (IQR) FCS for consumers was lower at 49 (35, 65) than for non-consumers 53 (36.5, 64). This difference was not statistically significant (p=0.526). There also was no difference between the average HDDS for consuming households (6.2±1.7) and for non-consuming households 6.2±1.5 (p=0.866). There was no significant association between consumption of edible insects and CDDS (p=0.802), HDDS (p=0.866), and FCS (p=0.585). In conclusion, this study showed that Gonimbrasia belina (mopani worms, madora, amacimbi) were the commonly consumed insect mostly as relish due to their palatable taste. Overall, the consumption of edible insects did not seem to improve diet diversity and food security indicators in this setting. National level studies with bigger sample sizes that investigate the contribution of edible insects to overall nutrient intake and dietary diversity are required. Furthermore, interventions to promote the consumption of edible insects, including their commercialization should adopt a social ecological approach to maximise impact. Key words: Entomophagy, food security, mopani worms, stunting, gender, Zimbabwe

Optimising mopane worm (Gonimbrasia belina) processing for improved nutritional and microbial quality.

Mopane worms (Gonimbrasia belina) is an important source of food and contribute to the nutrition of people who consume them. However, the traditional processing methods may have detrimental effects on the nutritional value and should also guarantee microbial quality. In this study, the nutritional composition and microbial quality of mopane worms processed under different boiling time (0-20 min) and drying temperature (40-60 °C) conditions were investigated and optimised using response surface methodology. An increase in the boiling time at the lowest drying temperature resulted in an increase in protein content and reduction in coliform counts. The optimum conditions of boiling for 20 min and drying at 40 °C resulted in mopane worms with a protein content of 49.4% DW and coliform counts <1.5 log cfu/g. In addition, high concentrations of crude fibre (13.6% DW) and fat (20.2% DW), as well as Fe (19.0 mg/100 g) and Zn (17.9 mg/100 g) were also recorded. A decrease in the total bacterial count, Escherichia coli and yeasts and moulds at the boiling time ≥20 min irrespective of the drying temperature suggested that exposure to heat reduced the microbial growth and contamination. Reduction of the mopane worms' moisture content (<7%) due to drying further slowed down the rate of microbial growth. The optimal processing conditions (boiling for 20 min and drying at 40 °C) are recommended for pretreatment of mopane worms prior to further processing into various products.

EFFECT OF CONVENTIONAL BULK PACKAGING MATERIAL, STORAGE TEMPERATURE AND DURATION ON QUALITY OF DRIED MOPANE WORM (Imbrasia Belina)

This study assessed the effect of conventional bulk packaging materials, storage time and temperature on qualityof dried mopane worm (Imbrasia belina). Changes in the quality of dried mopane worm (MW) were evaluatedin a 2 x 2 x 5 factorial experiment comprising packaging material (polypropylene woven (PP) and hessian sack),storage temperature (ambient temperature and 33 °C) and storage time (0, 30, 60, 90 and 120 days) with threereplications. Experimental data obtained was subjected to ANOVA and the means separated using the post hocTukey test at 5 % level of significance. Quality of traditionally processed dried MW was analysed using changesin physicochemical (ash, moisture, fat, protein and colour (L*, a*, b* and ∆E*), microbial (yeast and mouldand coliform) count and sensory (colour, taste, texture and overall acceptability) qualities. The proximatecomposition of dried MW was not significantly (p &gt; 0.05) affected by the interaction between the treatments.The interaction among treatments significantly (p &lt; 0.05) affected colour parameters L*, a*, b* and ∆E*. Therewas no significant (p &gt; 0.05) interaction between packaging materials, temperature and storage time on yeast,mould and coliform counts. The sensory quality of dried MW was not significantly (p &gt; 0.05) affected by theinteraction between the treatments thus indicating consumer acceptability. Deteriorative change in the qualityof dried MW was lower in PP than HS for the two levels of temperature over the duration of the experiment.

Mopane worm value chain in Zimbabwe: Evidence on knowledge, practices, and processes in Gwanda District.

Consumption of edible insects is a potential solution to the growing need for protein. However, the wild harvested edible insects' value chain faces several challenges including limited knowledge on indigenous practices in the harvesting and processing and lack of information on roles of the different actors in the chain. A case study of Gonimbrasia belina, colloquially referred to as the 'mopane worm', was conducted to understand and identify determinants of participation in the value chain of the edible caterpillar. A cross sectional study was conducted in Gwanda (a rural district in Zimbabwe) to (a) understand the indigenous knowledge on harvesting and processing methods, (b) explore value addition and the traditional beliefs surrounding the utilisation of the mopane worm. Results showed that consumers (81.7%), and harvesters (76.6%) were the main actors in the mopane worm value chain. Using the Ordinary Least Squares (OLS) model, the following were shown to be determinants of participation in the mopane worm value chain: (a) gender (b) household size (c) marital status (d) religion and (e) household assets. Two primary processing methods of harvested mopane worm were distinguished i.e., boiling and roasting on ambers. Results showed lack of diversity in mopane worm-based products. Current culturally acceptable processing techniques need improvement and standardization to support sustainable mopane worm processing while optimising nutrient bio-accessibility.

Congolese edible caterpillars, valuable sources of bioactive compounds with human health benefits

Insects are part of the regular diet of more than two billion people around the world and are not only delicacies. Insects provide great opportunities to replace meals but can have important additional benefits as well. In the Democratic Republic of the Congo (DRC), caterpillars are the most consumed insects, and they are consumed by more than 70% of the population throughout the year. The aim of this research was to report the microscopic features, mineral micronutrients, chromatographic fingerprints, antioxidant activities and peroxidase inhibition of edible Congolese caterpillars of the genusCinabra, Imbrasia andGonimbrasia from DRC. Microscopic analysis showed the presence of characteristic features, specific to each host plant of caterpillars, such as palisade cells, stomata, trichomes, sclereids, fibres, vessels, pollen and starch grains. Phytochemical screening by chromatographic techniques revealed the presence of phenolic acids, flavonoids and terpenes as major secondary metabolites. Elemental analysis on dry matter showed that studied caterpillars are insects containing significant amounts of micronutrients such as copper, magnesium, manganese, selenium and zinc.Gonimbrasia belina had the highest selenium, magnesium and zinc content (0.12 g/100 g, 0.17 g/100 g and 0.011 g/100 g, respectively) thanCirina forda, Cinabra hyperbius, Imbrasia truncata andImbrasia sp., C. forda andImbrasia sp. had the highest copper content (0.003 g/100 g).C. forda had the highest manganese content (0.006 g/100 g). All aqueous extracts displayed high radical-scavenging activities with IC50 values ranging from 10 to 80 μg/ml. Extracts showed the best cellular antioxidant activities on reactive oxygen species-induced chemiluminescence using L012 on human leucocytes 60 monocytes related to their IC50 values less than 0.5 μg/ml. In specific immuno-extraction followed by enzymatic detection of myeloperoxidase assay, all extracts of caterpillars exhibited a dose-dependent inhibitory effect on myeloperoxidase activity in the range concentrations of 1 to 20 μg/ml excepted extracts ofImbrasia epimethea,Imbrasia sp. andI. truncata. Our results showed that insects are not only valuable source of lipids, proteins and micronutrients such as selenium but also are sources of phytochemicals with therapeutic benefits.

Trace Metals, Crude Protein, and TGA-FTIR Analysis of Evolved Gas Products in the Thermal Decomposition of Roasted Mopane Worms, Sweet Corn, and Peanuts.

The thermal behavior of mopane worms (Imbrasia belina), roasted peanuts (Arachis hypogaea L.), and sweet corn (Zea mays L. saccharata) was investigated under inert conditions using the TGA-FTIR analytical technique heated from 64 to 844°C at a heating rate of 20°C/min. The degradation patterns of the food samples differed as sweet corn and peanuts exhibited four degradation stages 188, 248, 315, and 432°C and 145, 249, 322, and 435°C, respectively. Mopane worms displayed three (106, 398, and 403°C). The different decomposition patterns together with the types of evolved gases shown by FTIR analysis justified the varied biochemical and chemical composition of foods. The common evolved gas species between the food samples were H2O, CO2, P=O, CO, and CH4 but mopane worms showed two extra different bands of C-N and N-H. Higher volumes of evolved gases were recorded at temperatures between 276 and 450°C, which are higher than the usual cooking temperature of 150°C. This means that the food maintained its nutritional value at the cooking temperature. Mopane worms were found to contain twice and four times crude protein content than peanuts and corn, respectively. Only total arsenic metal was reported to be above threshold limits.