Polar lipids have an important role as emulsifiers and stability controlling agents in the food industry. The principal effects of the emulsifiers have been found to depend on the situation in which they are applied. They may act as stabilising additives, creating repulsive interactions between droplets. They may act as emulsifying agents, or they may destabilise emulsions by reducing protein adsorption at the oil/water interface. They may also destabilise emulsions by increasing wettability of fat crystals. Furthermore, they may form micellar or liposomal aggregates in the dispersion, influencing interactions and aggregation.