Food Allergen Carryover Within the Edible Insect Supply Chain: A Pilot Plant Investigation

The aim of this study was to assess whether edible insects reared on substrates containing food allergens can carry these allergens into the final product, and to evaluate the effectiveness of a pre-harvest fasting period in reducing this risk to provide consumer protection. Hermetia illucens larvae, chosen as the model species, were grown on substrates containing 10% of each of the following food allergens: peanut, almond, soy, celery, and gluten. At the end of the feeding period, larvae were sampled at T0 (end of feeding), T1 (24 h fasting), T2 (48 h fasting) and tested by real-time PCR and ELISA to detect allergen residues. Positive results were observed by real-time PCR for soy (mean Ct: 28.84 at T0, 29.4 at T1, 30.95 at T2), celery (mean Ct: 26.74 at T0, 26.90 at T1, 29.77 at T2) and almond (Ct 33.96 at T0 and mean Ct: 34.01 at T1). Soy presence was also confirmed by ELISA test. Insects may represent an alternative food source; however, their use requires careful evaluation due to the potential presence of allergens. Our results showed that insects may contain allergens originating from their feeding substrates, potentially triggering a response in allergic consumers.