What is lecithin?

Lecithin is the classic name for a group of chemical compounds called phosphatidylcholines. These are lipids (more precisely phospholipids) composed of fatty acids, glycerol, phosphoric acid and choline. Lecithins are components of the cell membranes of animal and plant life. They are accompanying substances in fats, most oils and are particularly rich in egg yolks and vegetable sperm cells.