Inoculation with black soldier fly larvae alters the microbiome and volatile organic compound profile of decomposing food waste

Abstract

The black soldier fly (BSF; Hermetia illucens) is used in sustainable processing of many types of organic waste. However, organic waste being decomposed by BSF produces strong odors, hindering more widespread application. The odor components and how they are produced have yet to be characterized. We found that digestion of food waste by BSF significantly alters the microbial flora, based on metagenomic analyses, and the odor components generated, as shown by thermal desorption gas chromatography mass spectrometry analysis. Inoculation with BSF significantly decreased production of volatile organic sulfur compounds (dimethyl disulfide and dimethyl trisulfide), which are known to be released during methionine and cysteine metabolism by Lactobacillus and Enterococcus bacteria. BSF inoculation significantly changed the abundance of Lactobacillus and Enterococcus and decreased microbial diversity overall. These findings may help in optimizing use of BSF for deodorization of composting food waste.

Mitigation Strategies against Food Safety Contaminant Transmission from Black Soldier Fly Larva Bioconversion

“…Finally, note that BSFL production itself produces undesirable wastes, including greenhouse gases, ammonia, and nitrous oxide [ 144 ], though arguably at lower rates than certain other waste management techniques or biomatter production methods. BSFL bioconversion produces odors that may necessitate management such as using air scrubber to minimize the smells coming from a fly facility, though the odors from BSFL production are generally lower than allowing wastes to decay [ 145 ]. Finally, BSFL production leaves behind undigested substrate, frass, exuviae, and dead adults, though the management and even valorization of these wastes is the subject of other reviews [ 146 , 147 , 148 ].…”