Comparison of DNA-based methods for the detection of meat feeding in <i>Alphitobius diaperinus</i> larvae

Insects are widely consumed as a source of protein, and several species of edible insects have been approved as novel foods for the European market in the last decade. The feeding of farmed animals, including edible insects, with products of animal origin is prohibited by the Transmissible Spongiform Encephalopathy (TSE) Regulation (EU) 999/2001 and the EU Animal By-Products (ABP) Regulation (EC) 1069/2009. Accordingly, methods are needed to detect and exclude insects fed on animal-derived products. Multiple tests based on the detection of DNA have been developed, but their use for the characterisation of insect-derived foods has not been assessed rigorously. Here, we compared a range of DNA-based methods for the detection of vertebrate DNA residues in edible insects. We fed larvae of the lesser mealworm (<i>Alphitobius diaperinus</i>) on diets containing pork and chicken meat, and analysed samples by multiplex PCR with Sanger sequencing, real-time PCR, DNA biochips, and both short-read and long-read next-generation sequencing. We present a workflow for the efficient detection of meat and/or poultry feeding in edible insects. This workflow can be used in validated food surveillance measures to protect consumers from deception and to ensure compliance with current regulations covering the feeding of edible insects.