Preparation of high purity egg yolk lecithin via low temperature precipitation method

Lecithin was extracted from fresh duck egg yolk liquid. During the extractin processes, factors such as egg yolk- ethanol ratio, hexane- acetone volume ratio and frozen temperature influencing lecithin yield and total phospholipid content were studied. The optimal extraction conditions were determined by single factors and orthogonal design experiments.It was as follows: the egg yolk-ethanol ratio 1∶4.5 ( g /mL) , hexane-acetone volume ratio 1∶2.5 and frozen temperature - 20℃, respectively. Under the optimized conditions, the results showed that lecithin yield and phospholipid content were 9.37% and 97.68% , respectively. The HPLC detection indicated that extracted yolk phospholipid had 77.42% of phosphotidylcholine and 18.47% of phosphotidylethanolamine, suggesting its feasiblity for industrial application.