Environmental Science

Valorisation of Organic Waste Through Black Soldier Fly: On the Way of a Real Circular Bioeconomy Process

The transition from a linear to a circular production system involves transforming waste (such as the organic fraction of municipal solid waste, OFMSW) into valuable resources. Insect-mediated bioconversion, particularly using black soldier fly (BSF) larvae, can offer a promising opportunity to convert OFMSW into protein-rich biomass. However, current regulatory restrictions limit the use of insect proteins for animal feed, prompting the exploration of other applications, such as the production of bioplastics. Here, we explored an innovative and integrated circular supply chain model which aims to valorise the OFMSW through BSF larvae for the production of biobased materials with high technological value. BSF larvae reared on the OFMSW showed excellent growth performance and bioconversion rate of the substrate. The use of well-suited extraction methods allowed the isolation of high-purity lipids, proteins, and chitin fractions, suitable building blocks to produce biobased materials. In particular, the protein fraction was used to develop biodegradable plastic films which showed potential for replacing traditional petroleum-based materials, with the promise to be fully recycle back to amino acids, thus promoting a circular economy process. Socioeconomic analysis highlighted values generated along the entire supply chain, and life cycle assessment pointed out that lipid extraction was the most challenging step. Implementation of more sustainable methods is thus needed to reduce the overall environmental impact of the proposed chain. In conclusion, this study represents a proof of concept gathering evidence to support the feasibility of an alternative supply chain that can promote circular economy while valorising organic waste.