Bio-refinery of insects with Pulsed electric field pre-treatment

Abstract

Insect production for food and feed purposes is rapidly emerging in Europe, in many cases relying on existing processing methods for blanching, freezing, drying, fractionating, but also seeking for more efficient and beneficial biomass treatment methods. Current study is aimed to explore the application of Pulsed electric fields (PEF) pretreatment of insect biomass (Hermetia illucens) for drying and oil extraction enhancement. The study demonstrates an increase in the drying rate of larvae pre-treated with PEF at 2 and 3 kV/cm; 5, 10 and 20 kJ/kg wet basis. No effect on fatty indices and amino acids profile were determined, but more free total amino acids especially at PEF with E = 2 kV/cm and 20 kJ/kg, were identified in press cake after pressing. Results from this study show, that PEF could be used as a pre-treatment before drying of insect mass to increase the drying rate or to decrease the drying time and the content of functional ingredients under gentle conditions. Slight increase in the oil yield after PEF treatment allows to propose this technique for oil extraction improvement.