In this work, three extraction methods: Soxhlet, microwave irradiation and ultrasonic irradiation for extraction of lipids from spent coffee grounds (SGC) were carried out using hexane and petroleum benzene as solvent. Also, supercritical fluid extraction (SFE) using CO2 under different conditions was used for comparison. Different methods of extraction with organic solvents showed significant differences in the extraction yields. However, no differences were found when a given method (e.g., microwave irradiation) was applied using different organic solvents. On the other hand, different extraction conditions from the various runs of SFE resulted in different extraction yields, all of which were higher than those of the other extraction methods using organic solvents except Soxhlet extraction. No significant differences were observed in the fatty acid compositions of the extracted oils using organic solvents. However, the fatty acid compositions of the oils extracted under different conditions of the SFE system indicated significant differences among several fatty acids.

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