Comparison of black soldier fly larvae pre-treatments and drying techniques on the microbial load and physico-chemical characteristics

Black soldier fly larvae (BSFL) are good candidates for upcycling wet organic residuals. Like other unprocessed raw animal products, BSFL require processing to prevent spoilage and degradation during storage facilitate their use as feed ingredients. In this study, hot-air drying freeze-drying were examined means ensure long-term preservation. Pre-treatments of larvae, such puncturing, blanching (40 s) scalding (2, 4, 6 8 min) in boiling water reduced times, most likely by affecting the integrity wax-coated cuticle that protects against desiccation. Overall, dried two six times faster using compared freeze-drying, pre-treatments proven effectively improve efficacy. Pre-treating followed a shorter time with hot air was effective at reducing primary secondary oxidation well darkening/browning (colour lightness, L* value) untreated control (raw-thawed) larvae. The also led significant reduction microbial load (3.21 4.83 log) dry product control. powder, produced from grinding thawed pre-treated 4 min before being (60 °C; h), had activity below 0.4. This relatively stable limited colour changes over 30-day period. These treatments resulted no detectable Salmonella Escherichia coli counts ranging 100 1000 cfu/g. powdered deemed suitable incorporate into pelleted under current regulations Canada.