Article ID: 24-03
The objective of this study was to determine the most efficient method for extracting oil from North Pacific krill (Euphausia pacifica). A rapid, single-step extraction using a mixture of acetone and ethanol was employed, and heat treatment was applied to the krill. Additionally, argon gas (Ar) was used during the extraction process to prevent lipid oxidation. The results demonstrated that heat treatment, both in air and under Ar conditions, resulted in higher lipid yields (2.14% and 2.12%, respectively). The extracted krill oil underwent analysis to determine the content of neutral lipids (NLs), polar lipids (PLs), and free fatty acids (FFAs). The krill oil heated under Ar conditions exhibited the highest NLs content but a lower amount of PLs. However, the FFAs content increased for both heated krill samples. Moreover, all krill oils exhibited high levels of n-3 polyunsaturated fatty acids, particularly elevated PLs content, which included icosapentaenoic acid (IPA) and docosahexaenoic acid (DHA) (18.83 – 26.64 and 26.45 - 33.87 g/100 g of lipid, respectively). These components were present in the extracts, with greater prominence observed for the Ar treatment condition. However, the peroxidation value and presence of thiobarbituric acid reactive substances indicated that heat induced lipid oxidation, thereby reducing the lipid quality. Therefore, heat treatment proved beneficial in enhancing lipid yield, although it also had a negative impact on lipid quality. Conversely, the use of Ar during extraction was found to delay lipid oxidation compared to other extraction methods.
