Co-solvent-modified supercritical carbon dioxide extractions of cholesterol and free amino acids from soft-shell turtle fish egg

摘要

This study examines the co-solvent-modified supercritical carbon dioxide (SC-CO2) extraction of cholesterol and free amino acids from soft-shell turtle fish egg powder.Extraction efficiencies and concentration factors of cholesterol and free amino acids in the SC-CO2 extracts were determined.Experimental data demonstrate that the initial extraction rate of cholesterol increased with temperature following static ethanol-modified SC-CO2 extractions at 300 bar.The 70.1% of extraction efficiency of cholesterol was obtained by continuous SC-CO2 extraction at 338 K and 300 bar.The response surface methodology was used to design SC-CO2 extractions of ethanol modified egg powder at 338 K,which revealed that increasing pressure and adding ethanol equally promoted the extraction efficiency of cholesterol.Concentration factors of cholesterol increased from 0.46% in egg powder to 7.88% in the SC-CO2 extracts.Experimentally designed SC-CO2 extractions of water-modified egg powder indicated that temperature substantially influenced the extraction efficiency of free amino acids.Concentration factors of free amino acids increased from 1.05% in egg powder to 29.46% in SC-CO2 extracts.