In situ solid phase extraction of phospholipids from heat-coagulated egg yolk by organic solvents

Heat-coagulated egg yolk packed into a chromatographic tube allows solvents to he led through with satisfactory flow rate effecting continuous extraction. This system is conceived as in situ solid phase extraction of egg yolk lipids with denatured yolk protein constituting the matrix. The separations of lipids that can be effected by elution with properly chosen solvents confirmed this conception. Several elution schemes are Presented. One of the most promising consists of initial elution with acetone yielding a lipid fraction containing all triglycerides and cholesterol and about 15% of the phospholipids, Subsequent elution with ethanol yields the remaining 85% phospholipid highly purified. The contents of long-chain polyunsaturated fatty acid of n-6 and n-3 series ill this product are 5-6 g/100 g and 6-7 g/100 g, respectively. The method described is discussed in relation to existing methodology for production of egg yolk phospholipids. (C) 2001 Academic Press.