Egg lecithin

[1] Gobley originally isolated lecithin from egg yolk—λέκιθος (lekithos) is 'egg yolk' in ancient Greek—and established the complete chemical formula of phosphatidylcholine in 1874.

Egg lecithin is usually extracted chemically using ethanol, acetone, petroleum ether but not benzene or hexane due to restrictions on residual solvents by the pharmaceutical regulations.

In aqueous solution, its phospholipids can form either liposomes, bilayer sheets, micelles, or lamellar structures, depending on hydration and temperature.

Commercial egg lecithin, specified in the United States National Formulatory (USP/NF) as used by pharmaceutical companies, is a highly purified mixture of phospholipids, devoid of triglycerides, cholesterol, or proteins.

Applications include: Egg lecithin is approved by the United States Food and Drug Administration with the status "generally recognized as safe"[5] and listed in the compendium.