Deciphering the Microbiota of Edible Insects Sold by Street Vendors in Thailand Using Metataxonomic Analysis

The aim of the present study was to investigate the microbiota of processed ready-to-eat (fried or boiled) edible insects sold by street vendors at local green markets in Thailand (Bangkok and Koh Samui). To this end, samples of 4 insect species (rhino beetle adults, silkworm pupae, giant waterbugs adults, and black scorpions) were collected and analyzed through viable counting and metataxonomic analysis. Enterobacteriaceae showed counts below 1 log cfu g⁻¹ in all samples, except for black scorpions, which showed elevated counts reaching up to 4 log cfu g⁻¹. Total mesophilic aerobes counts were up to 8 log cfu g⁻¹ in all the analyzed samples. Counts below 1 log cfu g⁻¹ were observed for <i>Escherichia coli</i>, <i>Staphylococcus aureus</i>, sulfite-reducing clostridia viable cells and spores, and <i>Bacillus cereus</i>. All the samples showed the absence of <i>Listeria monocytogenes</i> and <i>Salmonella</i> spp. According to metataxonomic analysis, 14 taxa were consistently present across all insect samples, including <i>Dellaglioa algida</i>, <i>Latilactobacillus curvatus</i>, <i>Latilactobacillus sakei</i>, Acetobacteraceae, <i>Apilactobacillus kunkeei</i>, <i>Bombilactobacillus</i> spp., Enterobacteriaceae, <i>Gilliamella</i> spp., <i>Lactobacillus</i> spp., <i>Lactobacillus apis</i>, <i>Streptococcus thermophilus</i>, <i>Lacticaseibacillus rhamnosus</i>, <i>Lactiplantibacillus plantarum</i>, and <i>Weissella</i> spp. Minority taxa included <i>Alcaligenes</i> spp., <i>Brochothrix thermosphacta</i>, <i>Psychrobacter</i> spp., <i>Staphylococcus saprophyticus</i>, <i>Lactobacillus melliventris</i>, <i>Pediococcus</i> spp., <i>Levilactobacillus brevis</i>, and <i>Snodgrassella alvi</i>.