Lecithin, or phosphatidylcholine, is an additive in culture media for the detection of microorganisms in the food and cosmetics industry and diagnostics.Lecithin is used as a natural emulsifier and to produce vesicle suspensions called liposomes. Phosphatidylcholines belong to the class of glycerophospholipids and contain choline as their main group. Lecithin, or phosphatidylcholine, is an additive in culture media for the detection of microorganisms in the food and cosmetics industry and diagnostics.Lecithin is used as a natural emulsifier and to produce vesicle suspensions called liposomes. Phosphatidylcholines belong to the class of glycerophospholipids and contain choline as their main group.