SEPARATION AND FORMATION OF EGG-YOLK OIL BY SOLUBILIZING THE LIPOPROTEINS OF SPRAY-DRIED EGG-YOLK INTO POLYPEPTIDES

Egg yolk oil was formed from a hen's egg without using the traditional charring method and organic solvents. By treating a spray-dried egg yolk suspension with a commercial crude enzyme preparation having protease and lipase activities, the lipids (egg yolk oil) could be easily separated, and a transparent solution of soluble polypeptides was obtained. When the enzyme preparation (4 mg) was added to a 5% spray-dried egg yolk (100 mg) suspension, the reaction mixture became transparent, and the egg yolk oil floated to the surface of the reaction mixture within 3 h. In the case of a 10% spray-dried egg yolk suspension, a transparent solution and egg yolk oil could be successfully obtained within 4 to 5 h by using a larger reaction vessel and a 0.2 M lactate buffer. About 87% of the total polypeptides in the initial reaction mixture was recovered from the transparent solution, while about 83% of the total phospholipids was recovered from the floating egg yolk oil.