Revalidation of Growth Kinetics Model of Black Soldier Fly Larvae (Hermetia illucens) with Fish Industrial Waste Substrate and Its Utilization

The interest in black soldier fly larvae (Hermetia illucens) has grown significantly due to their substantial bio-conversion capabilities, high nutritional content, and diverse product applications. They are now considered breakthrough solutions in waste management systems, particularly for organic matter. However, the timing of optimal maggot weight harvest in black soldier fly larvae cultivation is often overlooked. In Indonesia, maggot cultivators typically rely on their experience and knowledge of specific substrates for harvesting. Therefore, this study aimed to validate a proposed growth kinetics model for black soldier fly larvae using different substrate additions to assist maggot cultivators. One promising substrate for black soldier fly larvae cultivation is industrial fish waste, known for its high protein content, uniform substrate composition, abundance, and continuity. The fish waste used in this study was sourced from the tuna canning industry in Pasuruan Regency, East Java, Indonesia, specifically the fish heads and fish viscera. The results showed that the fish head substrate supported better growth of black soldier fly larvae compared to the fish viscera substrate. The kinetics model developed using the fish head substrate was then employed to evaluate the feasibility of scale-up, considering a substrate basis of 1,000 kg/day. The addition of 1,000 kg/day of fish head waste as substrate was found to be economically viable for scale-up, with key indicators such as the rate of investment, break-even point, shutdown point, pay-out time, and discounted cash flow rate of return values calculated as 12.8, 43.3, 28.0, 4.4 years, and 10.8, respectively. © The Author(s), under exclusive licence to Springer Nature B.V. 2024.