Transforming Coffee and Meat By-Products into Protein-Rich Meal via Black Soldier Fly Larvae ( Hermetia illucens )

In response to increasing food waste and the necessity for sustainable resource utilization, this study evaluated the effectiveness of black soldier fly ( Hermetia illucens ) larvae in converting a mixture of coffee and meat residues into protein-rich meal suitable for animal feed. A two-component mixture design optimized the substrate composition, followed by model validation and a comprehensive nutritional characterization of the larvae-derived protein. The larval meal contained 30–39 g of protein per 100 g (dry basis). The results indicated that increasing the meat residue content to 35% in the substrate maximized the protein yield. The optimized larval meal contained 52.9 g of protein per 100 g (dry basis) and favorable parameters such as moisture and fat, demonstrating a nutrient profile suitable for aquaculture feed. These findings suggested that Hermetia illucens larvae could convert agro-industrial by-products into high-quality protein. Coffee and meat residues served as suitable substrates for larval growth, supporting proper metabolic development and yielding a high bioconversion rate. This work contributes to the constant efforts in food waste valorization by integrating nutrient recovery processes into circular economy principles.