Investigating the Microbial Dynamics of Hermetia illucens Powder Throughout Rearing and Processing: An Integrated...

Area of Science:

• Food Science and Technology
• Microbiology
• Sustainable Agriculture

Background:

• Growing demand for sustainable protein sources positions Black Soldier Fly (BSF) larvae as a viable alternative.
• Microbiological safety is a critical concern for the widespread adoption of BSF larvae in food and feed.
• Understanding the microbial profile of BSF larvae and the impact of processing is essential for ensuring safety.

Purpose of the Study:

• To investigate the microbial diversity of BSF larvae.
• To compare the efficacy of two processing methods (boiling then drying vs. drying alone) on microbial loads.
• To assess the microbiological safety of BSF larvae for potential food applications.

Main Methods:

• 16S rRNA sequencing was employed to analyze microbial diversity.
• Culture-based methods quantified bacterial loads (mesophilic bacteria, spores, lactic acid bacteria, yeasts, molds, sulfite-reducing bacteria).
• A systematic review synthesized existing knowledge on BSF microbiota.

Main Results:

• High initial loads of mesophilic bacteria, spores, and lactic acid bacteria were observed in substrates and larvae.
• Boiling followed by drying significantly reduced most microbial loads, including yeasts, molds, and anaerobic sulfite-reducing bacteria.
• While key pathogens were absent, Campylobacter sp. detection in powders warrants attention for food safety.

Conclusions:

• Boiling and drying is more effective in reducing microbial loads in BSF larvae compared to drying alone.
• The presence of residual spore-forming bacteria (Bacillus, Clostridium) and Campylobacter highlights the need for optimized processing.
• Further research and stringent safety protocols are necessary to fully realize the potential of BSF larvae as a sustainable protein.