Possible presence of the allergenic ingredients milk and wheat in edible insects produced on milk and wheat rich substrates

Growing insects for food consumption contributes to sustainability as insects can grow efficiently on a wide variety of organic residual streams. These residual streams however contain a variety of proteins and – depending on their origin – can contain allergenic ingredients potentially triggering a response in patients. This study aimed to investigate the possible transfer of milk and wheat from residual streams to black soldier fly larvae (BSFL) and yellow meal worm (YMW). Using ELISA based test kits, transfer of wheat to BSFL but not to YMW larvae was shown. Concentrations of wheat in BSFL were not linear to concentrations in the different wheat based substrates, suggesting transfer is matrix depended. Four days of fasting BSFL showed to be sufficient to reduce the amount of wheat present in the larvae to concentrations below the detection limit of the assay. For milk, no transfer of the investigated substrates to BSFL was observed. For YMW the matrix reduced the signal of the test kit, hampering drawing conclusions about the milk transfer. In conclusion, only low transfer for wheat to BSFL was detected in amounts below the action levels set for allergic responses, indicating no allergic responses are expected in case of consumption.