Abstract:

The technologies of supercritical fluid extraction (SCF) with cosolvent or not and solvent extraction were applied to extract lecithin from egg yolk. The technics and extracting effect of three technologies were studied contrastively, and consequently the optimum method and technics were obtained. Three-level orthogonal array design was used to detect the technics parameters of SCF. Ultraviolet scanning (UV) and thin layer chromatography (TLC) were utilized to measure lecithin qualitatively and quantificationally. All extracts with the three methods contain impurity, of which SCF with cosolvent has the least impurity and its extraction rate is the highest, so SCF with cosolvent is considered as the optimum one among three extraction processes of lecithin. The appropriate conditions by SCF with cosolvent are 40 ℃, 20 MPa and 1.5 h under ethanol as carrier.

Key words: egg yolk, lecithin, supercritical extraction, solvent extraction, cosolvent