Lecithin is a substance found in egg yolks, milk, and some plant and animal tissues. It's been used as a medicine to treat various ailments for centuries, such as hypercholesterolemia (high cholesterol), liver disease, and asthma. Nowadays it's also incorporated into cosmetics like eye makeup and lipsticks. It's mostly made of three types of fatty acids: glycerophosphates (g-6-p), phosphatides (2-3-p), and triglycerides (t3). The glycerophosphates comprise about 40% of lecithin's weight.
Lecithin was first isolated from egg yolk in 1843, and for a while, the word "lecithin" was used to refer to any fat-like substance found in foods. It wasn't until 1907 that a chemist named Meyerowitz differentiated between two types of lecithin: one from animal sources, which he called "lipoid" (later called phosphatidylcholine), and the other from plants, which he called "cephalin" (later renamed cephalins). In 1936, Haarmann and colleagues took Meyerowitz's phosphatide to heart and determined that the name "cephalin" was inappropriate. They suggested that instead cephalins should simply be called "lecithin".
The word lecithin literally means ‘egg yolk like in Greek (meaning egg-white-like in Latin). The word was coined by Meyer in 1843. Lecithin is a mixture of various types of phospholipids, fatty acids, other materials, all determined by their structure. The most important types of phospholipids are phosphatidylcholine (40%) and phosphatidylethanolamine (15%). There are very minor amounts of the other types of phospholipids present, called phosphatidylinositol and a few others; glycerophosphates constitute about 15% of the lecithin. The triglycerides make up 25% of the lecithin, with the most dominant being oleic acid (omega-9). There are also fatty acids in small amounts that have been identified using mass spectrometry, but their structures haven't yet been confirmed.
Lecithin is a natural ingredient that molds and shapes food products, such as cookies, ice cream, chocolate bars, or milkshakes. Some of the challenges that lecithin producers are facing include increasing demand in China for soybean lecithin products as well as a limited supply of raw materials worldwide. The opportunities include introducing new product lines to address consumer demands for new flavors and for gluten-free foods
Lecithin is mainly used for food decorations and as an emulsifier in food products, such as milk, mayonnaise, salad dressings, salad creams, and chocolate. Lecithin is also used for producing pharmaceuticals (such as vitamins and liposomes) and feed supplements.
Soybean lecithin is a by-product of soybean oil production. Soybeans are the world's largest source of vegetable oil with a worldwide production estimate of over 300 million tons in 2014. In addition to being a raw material for vegetable oils (about 80% of the world's soybean production), soybeans are also a dietary protein source. Emulsifiers are used in a variety of food products such as margarine, salad dressing, chocolate, and baked goods.
The soybean refining business is highly consolidated around five large companies that control most of the world's supply. Lecithin is produced using the soybean press cake which is a by-product after extracting the oil from the beans. The extracted cake can be sold for animal feed or waste-derived fuel (such as biodiesel) while lecithin is produced by processing it further to remove impurities.