Substrate composition effects on black soldier fly larvae growth and bioconversion: A meta-analysis review

Abstract

As organic waste production rises, sustainable bioconversion technologies that adhere to the circular economy's tenets are needed. The larva of the Black Soldier Fly (Hermetia illucens, BSFL) has become an important organism for turning various organic wastes into nutrient-dense frass and biomass that is high in protein. Nonetheless, the substrate composition has a significant impact on this process's efficiency. 131 international empirical research published between 2015 and 2026 are compiled in this systematic review and meta-analysis to quantitatively evaluate the effects of substrate properties on BSFL growth and bioconversion efficiency. The results indicate that crude protein content and carbon-to-nitrogen (C/N) ratio are the main factors influencing larval biomass yield and feed conversion efficiency, with 18–22% protein and a C/N ratio of 20–25:1 producing the best results. Multivariate modelling reveals important relationships between important parameters and emphasizes the complementary advantages of combining substrate pretreatments, especially microbial inoculation and physical size reduction. Significant adaptability may be shown in the larvae's dietary makeup, which closely reflects substrate characteristics. This study demonstrates that BSFL bioconversion is governed by interacting substrate factors rather than single traits and provides a predictive framework for optimizing substrates for scalable and sustainable waste management.