Tasting the differences: Microbiota analysis of different insect-based novel food

Abstract

Traceability, quality and safety of edible insects are important both for the producers and the consumers. Today, alongside the burst of edible insects in western countries, we are facing a gap of knowledge of insect microbiota associated with the microbial ecosystems of insect-based products. In this context, High-Throughput DNA Sequencing (HTS) techniques can give insight into the carryover of insect microbiota into final food products. In this study, we investigated the microbiota composition of insect-based commercial food products, applying HTS techniques coupled with bioinformatic analysis. The work aimed to analyse the microbiota variability of different categories of some insect-based commercial food products made of A. domesticus (house cricket), T. molitor (mealworm beetle), and A. diaperinus (lesser mealworm or litter beetle), including commercial raw materials and processed food items, purchased via e-commerce from different companies. Our data revealed that samples cluster per insect species based on microbiota profile and preliminary results suggested that a small number of prevalent bacteria formed a "core microbiota" characterizing the products depending on the insect. This microbial signature can be recognized despite the different food processing levels, rearing conditions and selling companies. Furthermore, differences between raw and processed food made of the same insect or similar product produced by different companies was found. These results support the application of HTS analysis for studying the composition of insect-based commercial food products in a wider perspective, for food traceability and food quality control.

Keywords: DNA barcoding; DNA metabarcoding; High throughput sequencing; Insect; Microbiota; Processed food.