Insects as a waste-to-lipids platform for sustainable aviation fuel: Production, upgrading, and sustainability

The hydroprocessed esters and fatty acids (HEFA) pathway is a technically mature and commercially deployable process for producing sustainable aviation fuel (SAF) from lipid feedstocks. Nevertheless, the current supply of sustainable lipids is insufficient to meet the projected demand for SAF, emphasizing the need to identify alternative lipid sources. This review comprehensively evaluates the potential of insects as biological conversion platforms for transforming low-lipid organic wastes into lipid-rich biomass suitable for HEFA-based SAF production. The lipid contents and compositions of three representative insect species (black soldier fly larvae (BSFL), housefly larvae (HFL), and mealworms (MW)) are compiled and compared. The assessment indicates that fatty acid saturation and chain-length distributions are key determinants of the suitability of insect lipids for HEFA processing, influencing hydrogen demand and upgrading requirements. Among these species, BSFL-derived lipids show potential because of their high proportion of saturated fatty acids, especially lauric acid, which may reduce hydrogenation requirements and provide hydrocarbon chain lengths close to the jet-fuel range. Integration of insect-mediated waste conversion with existing HEFA infrastructure offers a potential route to expand the supply of waste-derived lipid feedstocks. However, the integrated waste-to-insect lipid-to-SAF pathway has not yet been demonstrated, and its environmental benefits and commercial feasibility require whole-pathway evaluation. Consequently, this review proposes insect-mediated lipid production as a complementary feedstock strategy for HEFA-based SAF and identifies feedstock consistency, contaminant control, experimental validation of catalytic upgrading and fuel properties, and integrated life-cycle and techno-economic assessments as priorities for practical implementation.