Black Soldier Fly Larvae Frass in the Bioeconomy: Properties, Applications, and Research Gaps- A Narrative Review

Abstract

The circular bioeconomy, which turns organic waste into useful resources, has noticed an increase in the value of insect byproducts. Frass from Hermetia illucens, the Black Soldier Fly, is one potential product. BSFL frass is a complex substance made up of various microorganisms, shed exoskeletons, undigested meal remnants, and insect excrement. Because of its unique composition, it can serve as a biostimulant and nutrient source, making it well-suited for sustainable soil fertility management. According to research, Frass stimulates nutrient cycling, improves soil stability and structure, increases microbial activity, and encourages plant growth. By lowering greenhouse gas emissions, reducing dependency on synthetic fertilizers, and promoting effective waste-to-resource systems in agro-industrial contexts, it enhances environmental sustainability and agronomic benefits. Its efficacy in sustainable agriculture is further enhanced by creative methods such as mixing Frass with compost, charcoal, or microbial inoculants. But there are still difficulties. Frass quality can vary due to differences in processing techniques, larval rearing circumstances, and substrate inputs. Broader adoption is further constrained by potential hazards from pollutants and infections, as well as regulatory concerns. Large-scale field validation, techno-economic evaluations, and harmonized international safety and quality standards are important research needs. All things considered, BSFL frass is a promising instrument for climate-smart circular food systems and nutrient recycling.