Soy lecithin is a by-product of soybean processing, produced by further manufacturing of crude soy oil. Lecithin is the gummy material contained in crude vegetable oils and removed by a degumming processing.
Soybeans are by far the most important source of commercial lecithin, and lecithin is the most important by-product of the soy oil processing industry because of its many applications in foods and industrial products. Soy lecithin is an excellent source of phospholipids, or phosphatides, for aquafeeds.
Phospholipids are the molecules that make up cell membranes.
The three main phosphatides in commercial soy lecithin are phosphatidyl choline (also called "pure" or "chemical" lecithin to distinguish it from the natural mixture), phosphatidyl ethanolamine (popularly called "cephalin"), and phosphatidyl inositols (also called inositol phosphatides). Commercial soy lecithin also typically contains roughly 30%-35% unrefined soy oil. Because it’s readily available from plentiful soybean crops all over the world, it’s the cheapest and easiest type of lecithin to mass manufacture.