The Use of Insects as Human Food in Zambia

Problem statement: The life cycle and culture structure of two commonly eaten worms in Zambia (Isoberlinia paniculata and Miombo/Mopani) were evaluated. The worms were grown on an artificial medium to evaluate the potential of producing them on a commercial scale. Approach: An interesting characteristic of the worms studied was that they reached their maximum weight and maximum length at the same time. Results: The larvae started to decrease in weight soon after reaching their maximum size suggesting that they should be harvested shortly before reaching their maximum length (36 days old). Only 10% mortality was observed with the older larvae of the Miombo/Mopani worm. A system where eggs are separated from adults and hatched in separate chambers would alleviate the danger of losing the population due to microbial infection. The high moisture content of the live larvae (60.5-60.9%) could cause handling and storage problems. Drying and grinding the larvae would reduce them to easily manageable forms and would improve their marketability as a novel food. The results obtained from this study showed the potential of using these insects as a protein source for human consumption. They had structured animal protein that contained the essential amino acids, lipids, vitamins, minerals and energy required for human growth and their nutrition contents are comparable to those of conventional foods. These worms are harvested from trees in Africa but the industry is facing droughts and overexploitation that has lead to local extinctions in several areas. Conclusion/Recommendations: Therefore, further research is required to evaluate their growth on low substrates and to assess the effects of environmental parameters such as temperature, relative humidity, CO₂ and heat production on food consumption and protein yield and quality. This information will aid in the design of an optimal commercial insect production system. Appropriate processing and marketing procedures would also insure the sustainability of the industry.