Comparison of Growth and Composition of Black Soldier Fly (Hermetia illucens L.) Larvae Reared on Sugarcane By-Products and Other Substrates

Black soldier fly larvae (BSFL) can convert organic waste into high-quality biomass. In this study, we tested the potential of sugarcane by-products as a food source for BSFL and compared larval development and nutritional value with some other organic substrates. Seven different substrates were used, including carrot pomace (C), carrot pomace and leftover bread (CB) (50/50), bagasse and vinasse (BV), bagasse and molasses (BM), bagasse, vinasse, and molasses (BVM), a mixture of all the above treatments (MX), and university canteen leftovers (UCLs). The larval weight and length were measured for two weeks from day 5 to 19. Then, the BSFL were harvested and analyzed for dry matter, crude protein, oil, ash, mineral, and fatty acid composition. Larval weight and length varied depending on the feeding substrate provided. University canteen leftovers resulted in the BSFL having at least 18% greater length (17.00 mm) and 56% greater weight (3.15 g) compared to other treatments. The highest amounts of protein (38.9%) and oil (39.06%) were observed in the UCL treatment, while the BV treatment larvae had the highest quantities of ash (28.9%) and dry matter (28.0%). The fatty acid profile of the BSFL revealed three-times-higher levels of saturated fatty acids than unsaturated fatty acids in the UCL treatment and was at least twice as high in other treatments. Overall, the BSFL had the best growth on the UCL substrate, and the combination of bagasse and vinasse (BV) was the most appropriate substrate for BSFL development among the sugarcane by-products.