In cooking, it is often necessary to combine oil and water-based ingredients. Based on the adage “oil and water don’t mix,” this would be quite a feat! However, lecithin, an emulsifier found in egg yolks, binds with ingredients such as water and oil, allowing them to mix and making many recipes possible. Without it, we would not have stable mayonnaise, margarine, creamy eggnog, nut butters, gravies or fluffy sauces!
Lecithin’s binding power comes from its molecular structure- one part being hydrophobic (water fearing), making it soluble in oils or fats, while the other part is hydrophilic (water loving), making it soluble in water. This reduces the surface tension of oils or fats and water molecules, allowing them to mix together more easily. In cakes or baked goods, lecithin can also add fat content to recipes and make them more moist, as well as acting as a preservative.
So what is lecithin? Lecithin, or phosphatidylcholine, is a fat molecule that contains important nutrients such as choline, which is a biologically valuable substance that every cell of the body needs. Choline has been shown to play an important role in fetal and infant brain development; pregnant and breastfeeding women require 450mg and 550mg of choline per day, respectively. Eggs are an excellent source of choline and provide about 125mg, or roughly one quarter of the recommended amount, per large egg.
So next time you crack an egg in your favorite recipe, think of lecithin and its many culinary and health benefits!