Olive Pomace and Melon Bio-Byproducts from the Agribusiness: A Promising Combination for the Sustainable Production of Animal Protein from BSF Larvae

The black soldier fly (Hermetia illucens) offers a sustainable solution for converting agro-industrial bio-byproducts into high-quality animal protein. This study evaluated two abundant residues from the Santarém region of Portugal, melons and olive pomace, as substrates for larval rearing. Two experimental diets were formulated using these byproducts and compared to a standard Gainesville-based control diet, with all diets adjusted for moisture and protein content. Larval performance was assessed through metrics including individual weight, biomass, feed conversion ratio (FCR) and bioconversion rate. Diets 1 (melon-based) and 2 (melon + 55.2% olive pomace) yielded larval biomass of 1.82 ± 0.17 kg and 1.80 ± 0.11 kg per box, respectively, compared to the control (1.60 ± 0.03 kg). The FCRs were lower in the experimental diets (7.47 ± 0.75 and 7.53 ± 0.49) than in the control (8.42 ± 0.16), and the bioconversion rates were higher (13.48% and 13.31% vs. 11.88%). These results suggest that combining melon and olive pomace improves larval development and conversion efficiency, compared to the literature. This study demonstrates the potential of using local bio-byproducts to enhance insect-based protein production while reducing waste and supporting circular economy practices.