In view of future expected industrial bio-fractionation of insects, we investigated the influence of extraction
methods on chemical characteristics of insect lipids. Lipids from Tenebrio molitor, Alphitobius diaperinus, Acheta
domesticus and Blaptica dubia, reared in the Netherlands, were extracted by two industrial extraction processes
(aqueous and Soxhlet) and one laboratory method (Folch extraction). Chemical characterization in terms of
fatty acid composition (GC-FID), triacylglycerol profile (GC) and lipid classes (TLC) was performed on all the
extracted lipids. The major findings on lipid chemical characterization were the following: (1) T. molitor had
the highest lipid content around 13%; (2) the highest yield was obtained using Folch extraction, and the lowest
yield using the aqueous method (from 19 to 60% related to the lipid recovery of Folch extraction); (3) ω-3 fatty
acids,which are related to health benefits, weremost abundant in lipids fromaqueous extraction,whileω-6 fatty
acids were most abundant in Folch extractions, except for B. dubia; (4) lipids from Folch and Soxhlet extractions
contained free fatty acids and partial glycerides, which were absent in aqueous extractions; (5) triacylglycerol
distribution is similar among insect species, with high levels of ECN 50–54 and low amounts of ECN 36–38. In
conclusion, aqueous extraction gave the lowest lipid yield, but provided a lipid extract low in ω-6/ω-3 ratio
and with less polar lipids than Soxhlet and Folch extractions. These characteristics are desirable in edible lipids.
This is the first time that the triacylglycerol profile of insect lipids is reported. It is also the first time that
C18:1 and C18:2 are reported as separated isomers and that trans isomers of C16:1 and C18:1 are reported in
insect lipids