Zwitterionic surfactants are surfactants that can carry a zero net charge so that surfactant molecule is essentially neutral.

What are examples of surfactants?

Sodium stearate is a good example of a surfactant. It is the most common surfactant in soap. Another common surfactant is 4-(5-dodecyl)benzenesulfonate. Other examples include docusate (dioctyl sodium sulfosuccinate), alkyl ether phosphates, benzalkaonium chloride (BAC), and perfluorooctanesulfonate (PFOS).

Is lecithin a zwitterionic surfactant?

Phospholipids are common zwitterionic surfactants that have Generally Regarded As Safe (GRAS) status, which permits their use in food. However, some phospholipids, such as lecithin, are too lipophilic and have a high critical packing parameter (described later), making their incorporation into MEs difficult.