Comparison of volumetric and surface decontamination techniques for innovative processing of mealworm larvae (Tenebrio molitor)

Abstract

Abstract For food and feed safety of edible insects, effective decontamination methods need to be evaluated and developed. Traditional decontamination and preparation methods were reviewed and thermal and innovative inactivation methods for the decontamination of mealworm larvae were evaluated and compared. The impact of the surface decontamination techniques direct and indirect plasma treatment, and of volumetric methods such as high hydrostatic pressure treatment (400, 500, and 600 MPa) and thermal treatments (45 °C and 90 °C) for up to 15 min on the surface microbial load and on the overall microbial count of mealworm larvae ( Tenebrio molitor ) have been investigated. It was found that the indirect plasma treatment was an effective means for the surface decontamination of mealworm larvae, whereas high hydrostatic pressure at 600 MPa and thermal treatments in a water bath at 90 °C in comparison resulted in the highest reduction of the overall count. It is thus concluded that volumetric methods are favorable for the inactivation of the gut microbiota of insects. Industrial relevance Edible insects represent a valuable alternative protein source that could contribute to food and feed security and are industrially mainly unexploited. For a successful marketing of edible insects food and feed safety has to be ensured and effective decontamination methods need to be developed.