title: Microbial community assessment of mealworm larvae (Tenebrio molitor) and grasshoppers (Locusta migratoria migratorioides) sold for human consumption.
abstract: In Western countries, the popularity of edible insects as an alternative animal protein source is increasing. Nevertheless, there is a lack of profound insight into the microbial safety and shelf life of living insects sold for human consumption. The purpose of this study was to characterise the microflora of fresh edible mealworm larvae and grasshoppers in a quantitative and qualitative way. Therefore, culture-dependent analyses (the total viable aerobic count, Enterobacteriaceae, lactic acid bacteria, yeasts and moulds, and bacterial endospores) and next-generation sequencing (454amplicon pyrosequencing) were performed. High microbial counts were obtained for both insect species. Different insect batches resulted in quite similar microbial numbers, except for bacterial endospores. However, the bacterial community composition differed between both insect species. The most abundant operational taxonomic unit in mealworm larvae was Propionibacterium. Also members of the genera Haemophilus, Staphylococcus and Clostridium were found. Grasshoppers were mainly dominated by Weissella, Lactococcus and Yersinia/Rahnella. Overall, a variety of potential spoilage bacteria and food pathogens were characterised. The results of this study suggest that a processing step with a microbiocidal effect is required to avoid or minimize risks involved with the consumption of edible insects.
authors.affiliation: KU Leuven, Faculty of Engineering Technology, Department of Microbial and Molecular Systems (M²S), Lab4Food, Campus Geel, B-2440 Geel, Belgium; KU Leuven, Leuven Food Science and Nutrition Research Centre (LFoRCe), B-3001 Leuven, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Stoops
authors.affiliation: KU Leuven, Faculty of Engineering Technology, Department of Microbial and Molecular Systems (M(2)S), Laboratory for Process Microbial Ecology and Bioinspirational Management (PME & BIM), Campus De Nayer, B-2860 Sint-Katelijne-Waver, Belgium; KU Leuven, Leuven Food Science and Nutrition Research Centre (LFoRCe), B-3001 Leuven, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: Crauwels
authors.affiliation: KU Leuven, Faculty of Engineering Technology, Department of Microbial and Molecular Systems (M(2)S), Laboratory for Process Microbial Ecology and Bioinspirational Management (PME & BIM), Campus De Nayer, B-2860 Sint-Katelijne-Waver, Belgium; KU Leuven, Leuven Food Science and Nutrition Research Centre (LFoRCe), B-3001 Leuven, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Waud
authors.affiliation: KU Leuven, Faculty of Engineering Technology, Department of Microbial and Molecular Systems (M²S), Lab4Food, Campus Geel, B-2440 Geel, Belgium; KU Leuven, Leuven Food Science and Nutrition Research Centre (LFoRCe), B-3001 Leuven, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Claes
authors.affiliation: KU Leuven, Faculty of Engineering Technology, Department of Microbial and Molecular Systems (M(2)S), Laboratory for Process Microbial Ecology and Bioinspirational Management (PME & BIM), Campus De Nayer, B-2860 Sint-Katelijne-Waver, Belgium; KU Leuven, Leuven Food Science and Nutrition Research Centre (LFoRCe), B-3001 Leuven, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Lievens
authors.affiliation: KU Leuven, Faculty of Engineering Technology, Department of Microbial and Molecular Systems (M²S), Lab4Food, Campus Geel, B-2440 Geel, Belgium; KU Leuven, Leuven Food Science and Nutrition Research Centre (LFoRCe), B-3001 Leuven, Belgium. Electronic address: leen.vancampenhout@kuleuven.be.
authors.forename: L
authors.initials: L
authors.lastname: Van Campenhout
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D044822:Biodiversity; D003257:Consumer Product Safety; D059022:Food Safety; D005658:Fungi / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D006801:Humans; D007814:Larva / Q000382:microbiology*; D048188:Locusta migratoria / Q000382:microbiology*; D013712:Tenebrio / Q000382:microbiology*
keywords: Culture-dependent analyses; Edible insects; Grasshoppers; Mealworm larvae; Next-generation sequencing