Impact of lipid extraction on the dearomatisation of an Eisenia foetida protein powder

Delipidation was studied as a way to dearomatise a non-conventional protein powder obtained from Eisenia foetida earthworms. In the first step, we studied the impact of several factors such as solvent type, extraction method and particle size on the yield of extracted lipids. Lipid extraction from samples was considerably improved using an ultrasound method with a chloroform/methanol mixture and small particle size. In the second step, the volatile compounds were extracted from the delipidated protein powder by the SAFE extraction method and by the HS-SPME method, and were further analysed by GC–MS. The chloroform/methanol mixture and the ultrasound method extracted a wide range of volatile compounds very efficiently. Moreover, whatever method was used to extract the lipids, the volatile compounds detected in the headspace of the delipidated powder represented less than ¼ of the volatile compounds detected in the headspace of the regular powder.