Cold storage and cryoprotectant accumulation to prolong shelf-life in black soldier fly, Hermetia illucens

The industrial scaling of Hermetia illucens production for waste bioconversion and alternative protein provision is severely constrained by logistical challenges in breeding stock preservation and long-distance transport. To address this, we developed and optimized stage-specific cold storage protocols to significantly prolong the shelf-life of H. illucens. Through a multi-stage experimental approach, we determined that 1-d-old eggs can be successfully stored at 17 °C for 10 d with 50.0% hatchability, larvae retained a 72.8% survival rate after 30 d at 15 °C, and prepupae maintained a 75.3% eclosion rate following 60 d at 14 °C. In addition, a key innovation of this study was the strategic use of dietary cryoprotectants to markedly enhance cold tolerance. Under a severe discriminating temperature (-5 °C), supplementation with 4% proline and 0.5% trehalose elevated larval survival to over 80%. Furthermore, at the chronic stress of the developmental threshold (12 °C), 3% glycerol, nearly doubled larval survival rates compared to the control. The application of these optimized cryoprotectants with stage-specific storage temperatures effectively mitigated sublethal fitness costs, ensuring high post-storage performance in survival, pupation, eclosion, and reproductive output. Our findings provide a robust, comprehensive framework for synchronizing H. illucens supply chains, enabling viable long-distance transport, and facilitating the reliable industrial scaling of H. illucens production for the circular bioeconomy.