Insects need a sufficient quantity of macro- and micronutrients in their diet for maximising their growth, development, and reproduction. To achieve high efficiency in the mass production of a particular insect species, the quality of the diet given must be considered, both in terms of its chemical (nutrients) and physical (hardness and form) characteristics. Black soldier fly (BSF), Hermetia illucens (L.) (Diptera: Stratiomyidae), is a beneficial insect widely reared due to its easy and cost-effective maintenance. An example of the end-product of BSF larvae (BSFL) is known as BSF oil, which can be used for animal feed, raw material in bar/liquid soap, and biodiesel. To obtain the best quality of oil produced from BSFL, finding an optimal substrate through diet mixing or manipulation is quite necessitated. Fatty acids with more than 18 carbons should be found in the substrate to be absorbed into the fat of BSFL to obtain a high-quality oil. There is a positive correlation between the fatty acid concentration in the substrate and the concentration in BSFL, that the concentration in BSFL is influenced by the concentration in the substrate. This emphasises the importance of the substrate’s fatty acid content in incorporating these fatty acids into BSF oil. Although the oils produced by the insect are especially high in medium-chain fatty acids and monounsaturated fatty acids, yet, to produce on such a large scale requiring further investigations.

Abstract

In Africa, food insecurity seems to be a continual problem as a result of various factors such as extreme poverty, water scarcity, land degradation, and climate change. As a result, chronic hunger and malnutrition are still prevalent in many African countries. Consequently, the utilization of available and affordable natural food sources is needed to accommodate the energy and nutritional requirements of the people, such as edible insects. Edible insects are abundant and locally available throughout Africa, hence could be utilized as low-cost, nutritious, and sustainable foods. Around 500 species have been recorded in sub-Saharan Africa out of the 2,100 known edible insect species worldwide. The consumption of insects, also known as entomophagy, has been historically practiced by indigenous people of Africa. To date, edible insects are seen in Africa as a good opportunity, particularly for rural households, to improve their livelihoods at an economic and nutritional level. Edible insects are a great source of energy and nutrients – and their rearing only requires a small amount of water, land and feeding resources. Entomophagy may also serve as an ecologically sound control measure for insect pests, such as locusts, that periodically wreak havoc on agricultural fields. The combination of being a highly nutritious food source and having economic advantages made edible insects very attractive in all the African regions. Their promotions into the diet would ameliorate the well-being of the population and boost economic growth in Africa. However, African countries need local and regional legal frameworks to achieve smooth functioning of marketing of edible insects and their products.

Nutritious and sustainable food sources are much needed to compensate for the rising demand for food due to the ever-growing human population. The idea of using insects as potential future foods is getting more attention globally. The consumption of insects or entomophagy offers several advantages other than fulfilling human nutritional and energy requirements. By considering climate change and the reduction in arable land and water, entomophagy and insect farming is regarded to be more environmentally friendly than animal husbandry. Among thousands of edible insect species, grasshoppers and locusts may become viable options as novel foods. In this review, all edible grasshopper and locust species are listed along with the countries where they are consumed. The nutritional value and nutraceutical and pharmaceutical properties of some commonly consumed grasshoppers and locusts are overviewed. Lastly, factors affecting the consumer acceptance of grasshoppers and locusts as emerging foods are discussed, and steps to incorporate the insects into consumers’ tables are given. Based on this review, there are at least 120 species of edible grasshopper and locust species. They are packed with nutrients and antioxidant substances, and are widely consumed across African and Asian countries and in certain parts of America. However, the rejection of grasshoppers and locusts as foods is still prevalent among consumers in western countries due to the stigma surrounding insects. Raising the consumers’ awareness through the dissemination of the health and environmental benefits of entomophagy could be a strategic way to increase the adoption of grasshoppers and locusts as foods.