MICROBIOLOGY AND NUTRITIONAL COMPOSITION OF AN EDIBLE LARVA (BUNAEA ALCINOE STOLL) OF THE NIGER DELTA

Foodborne Diseases in the Edible Insect Industry in Europe-New Challenges and Old Problems

Insects play a key role in European agroecosystems. Insects provide important ecosystem services and make a significant contribution to the food chain, sustainable agriculture, the farm-to-fork (F2F) strategy, and the European Green Deal. Edible insects are regarded as a sustainable alternative to livestock, but their microbiological safety for consumers has not yet been fully clarified. The aim of this article is to describe the role of edible insects in the F2F approach, to discuss the latest veterinary guidelines concerning consumption of insect-based foods, and to analyze the biological, chemical, and physical hazards associated with edible insect farming and processing. Five groups of biological risk factors, ten groups of chemical risk factors, and thirteen groups of physical risks factors have been identified and divided into sub-groups. The presented risk maps can facilitate identification of potential threats, such as foodborne pathogens in various insect species and insect-based foods. Ensuring safety of insect-based foods, including effective control of foodborne diseases, will be a significant milestone on the path to maintaining a sustainable food chain in line with the F2F strategy and EU policies. Edible insects constitute a new category of farmed animals and a novel link in the food chain, but their production poses the same problems and challenges that are encountered in conventional livestock rearing and meat production.

Diversity, Host Plants and Potential Distribution of Edible Saturniid Caterpillars in Kenya

Simple Summary

Edible insects are a traditional food source with economic benefits in sub-Saharan Africa. Caterpillars are the most popular edible insects in this region. We focus on caterpillars in the family Saturniidae. Saturniids are big colorful caterpillars with spines on their bodies, usually found in shrubs and trees. They are rich in proteins, vitamins, and minerals. Despite their economic importance, little is known about their diversity, host plants, distribution, and potential effect of climate change on edible saturniid caterpillars in Africa. The aim of this study is to identify edible saturniids, their host plants, their current distribution and to predict the possible effects of climate change on their distribution. We documented seven species of edible saturniids namely Gonimbrasia zambesina, Gonimbrasia krucki, Bunaea alcinoe, Gonimbrasia cocaulti, Gonimbrasia belina, Gynanisa nigra and Cirina forda. These caterpillars mostly occur twice a year during the rainy seasons and feed on specific host plants. Predictive distribution models revealed that B. alcinoe, and C. forda are mostly found in tropical and sub-tropical regions in Africa. However, climate change could cause a slight decrease in their population by the year 2050. This information will guide conservation efforts and ensure sustainable use of edible saturniid caterpillars as food.

Abstract

The promotion of edible insects, including saturniid caterpillars as potential food source is widely gaining momentum. They are adequately rich in nutrients such as proteins, amino acids, fatty acids, and micronutrients. Despite saturniids being a traditional food source with economic benefits, information on their diversity, host plants and their potential distribution in Africa are lacking, which this study seeks to address. Edible saturniids and their host plants were characterized using specific primers (LepF1/LepR1 and 3F_KIM_F/1R_KIM_R, respectively). Maximum entropy (MaxENT) and GARP (genetic algorithm for ruleset production) models were used to characterize the potential distribution of commonly consumed saturniids under current and future climate scenarios. Seven species of saturniids were recorded from 11 host plants in Kenya: Gonimbrasia zambesina, Gonimbrasia krucki, Bunaea alcinoe, Gonimbrasia cocaulti, Gonimbrasia belina, Gynanisa nigra and Cirina forda. Two morphotypes of G. zambesina and B. alcinoe were recorded. These saturniid caterpillars occur twice a year except for G. cocaulti. Predictive models revealed that tropical and subtropical regions were potentially suitable for B. alcinoe and C. forda. The information generated from this study would be important to guide conservation efforts and their sustainable utilization as food in Africa.

Safety of Mealworm Meal in Layer Diets and their Influence on Gut Morphology

Simple Summary

There is limited research on the use of the mealworm meal in laying hens’ diets and effects on relative organ weights, caecum microbiota, ileum morphology and digesta viscosity. All these parameters can affect the performance of animals, i.e., the laying and quality of eggs. The mealworm meal is a relatively new feedstuff, where it is necessary to exclude a possible harmful effect. Insect products have a beneficial nutrient content, but there are issues of stability, shelf life, storage and contamination, which could, in the case of negative properties, affect the morphology of the digestive tract, cause liver damage and, as a result, affect the animal performance parameters. The main objective of this study was to verify the safety of the mealworm meal in the feed of laying hens from 17–42 weeks of age. Therefore, the feed mixtures were tested in terms of microbiological stability, fungal and mycotoxin content and selected parameters of hens’ intestinal morphology and physiology were monitored. Feed mixtures with proportions of insect products were microbially stable even after four months. Based on the results of this study, use of two to five percent of mealworm meal in hen′s diet may be used as a sustainable and safe protein feed.

Abstract

The main objective of this study was to verify the safety of mealworm meal in the feed of laying hens from 17 to 42 weeks of age. Therefore, the feed mixtures were tested in terms of microbiological stability, fungal and mycotoxin content and selected parameters of hens’ intestinal morphology and physiology were monitored. The experiment was carried out with 30 Lohmann Brown Classic hens. Hens were divided by body mass into three equal groups with 10 replicates per treatment. The two experimental groups received feed mixtures containing 2% and 5% yellow mealworm (Tenebrio molitor L.) meal. The third group was a control group which had 0% of mealworm meal in the diet. Diets with 2% and 5% of mealworm meals did not affect the length of villi and microbiome of the caecum. The highest digesta viscosity from the ileum was found in the group with 5% mealworm, which may indicate a slower passage of the digesta through the digestive tract. Based on our results, it may be concluded that the proportion of mealworm meals does not deteriorate the quality of feeds. Mealworm meal does not negatively affect microbial stability in experimental feeds. Therefore, it can be recommended the two and (or) five percent of mealworm meal inclusion in hen’s diet.

Current knowledge on the microbiota of edible insects intended for human consumption: A state-of-the-art review

Because of their positive nutritional characteristics and low environmental impact, edible insects might be considered a 'food of the future'. However, there are safety concerns associated with the consumption of insects, such as contaminating chemical and biological agents. The possible presence of pathogenic and toxigenic microorganisms is one of the main biological hazards associated with edible insects. This review presents an overview of the microbiota of edible insects, highlighting the potential risks for human health. Detailed information on the microbiota of edible insects from literature published in 2000-2019 is presented. These data show complex ecosystems, with marked variations in microbial load and diversity, among edible insects as well as stable and species-specific microbiota for some of the most popular edible insect species, such as mealworm larvae (Tenebrio molitor) and grasshoppers (Locusta migratoria). Raw edible insects generally contain high numbers of mesophilic aerobes, bacterial endospores or spore-forming bacteria, Enterobacteriaceae, lactic acid bacteria, psychrotrophic aerobes, and fungi, and potentially harmful species (i.e. pathogenic, mycotoxigenic, and spoilage microbes) may be present. Several studies have focused on reducing the microbial contamination of edible insects by applying treatments such as starvation, rinsing, thermal treatments, chilling, drying, fermentation, and marination, both alone and, sometimes, in combination. Although these studies show that various heat treatments were the most efficient methods for reducing microbial numbers, they also highlight the need for species-specific mitigation strategies. The feasibility of using edible insects as ingredients in the food industry in the development of innovative insect-based products has been explored; although, in some cases, the presence of spore-forming bacteria and other food-borne pathogens is a concern. Recent studies have shown that a risk assessment of edible insects should also include an evaluation of the incidence of antibiotic-resistance (AR) genes and antibiotic-resistant microorganisms in the production chain. Finally, as proposed in the literature, microbial hazards should be limited through the implementation of good hygienic practices during rearing, handling, processing, and storage, as well as the implementation of an appropriate HACCP system for edible insect supply chains. Another issue frequently reported in the literature is the need for a legislative framework for edible insect production, commercialisation, and trading, as well as the need for microbiological criteria specifically tailored for edible insects. Microbiological criteria like those already been established for the food safety and hygiene (e.g. those in the European Union food law) of different food categories (e.g. ready-to-eat products) could be applied to edible insect-based products.

Postharvest processes of edible insects in Africa: A review of processing methods, and the implications for nutrition, safety and new products development

In many African cultures, insects are part of the diet of humans and domesticated animals. Compared to conventional food and feed sources, insects have been associated with a low ecological foot print because fewer natural resources are required for their production. To this end, the Food and Agriculture Organization of the United Nations recognized the role that edible insects can play in improving global food and nutrition security; processing technologies, as well as packaging and storage techniques that improve shelf-life were identified as being crucial. However, knowledge of these aspects in light of nutritional value, safety, and functionality is fragmentary and needs to be consolidated. This review attempts to contribute to this effort by evaluating the available evidence on postharvest processes for edible insects in Africa, with the aim of identifying areas that need research impetus. It further draws attention to potential postharvest technology options for overcoming hurdles associated with utilization of insects for food and feed. A greater research thrust is needed in processing and this can build on traditional knowledge. The focus should be to establish optimal techniques that improve presentation, quality and safety of products, and open possibilities to diversify use of edible insects for other benefits.

Microbiological Load of Edible Insects Found in Belgium

Edible insects are gaining more and more attention as a sustainable source of animal protein for food and feed in the future. In Belgium, some insect products can be found on the market, and consumers are sourcing fresh insects from fishing stores or towards traditional markets to find exotic insects that are illegal and not sanitarily controlled. From this perspective, this study aims to characterize the microbial load of edible insects found in Belgium (i.e., fresh mealworms and house crickets from European farms and smoked termites and caterpillars from a traditional Congolese market) and to evaluate the efficiency of different processing methods (blanching for all species and freeze-drying and sterilization for European species) in reducing microorganism counts. All untreated insect samples had a total aerobic count higher than the limit for fresh minced meat (6.7 log cfu/g). Nevertheless, a species-dependent blanching step has led to a reduction of the total aerobic count under this limit, except for one caterpillar species. Freeze-drying and sterilization treatments on European species were also effective in reducing the total aerobic count. Yeast and mold counts for untreated insects were above the Good Manufacturing Practice limits for raw meat, but all treatments attained a reduction of these microorganisms under this limit. These results confirmed that fresh insects, but also smoked insects from non-European trades, need a cooking step (at least composed of a first blanching step) before consumption. Therefore, blanching timing for each studied insect species is proposed and discussed.