Lecithin

Lecithin is a naturally occurring mixture of the phosphatides of choline, ethanolamine and inositol. The federal regulations describe commercial lecithin as obtained from soybean, safflower or corn oil processing, and it is sold as a thick, amber liquid or a granular powder.

As an emulsifier it helps oil and water mix and stay mixed. Chocolate makers add a little to keep melted chocolate fluid and smooth, bakers use it to keep doughs and batters tender and to help them mix evenly, and it is also found in pan-release sprays and in whipped toppings.

Soy and sunflower versions are both common and behave similarly, so one can generally replace the other.