Lecithin

Almost all chocolate contains trace amounts of lecithin. Lecithin is extracted from soybeans and is well known as an emulsifier. Because chocolate contains no water, it is not an emulsion, but rather a suspension of solid particles in fat. The function of lecithin in chocolate is not to emulsify but to reduce viscosity; a very small amount of lecithin improves melted chocolate’s ability to flow. Lecithin reduces viscosity only up to a point, however. When the lecithin in chocolate exceeds about 0.3 percent, viscosity begins to increase again, so adding more lecithin to chocolate will typically make it thicker, not thinner. Chocolate manufacturers usually add the amount of lecithin that will give them the maximum advantage in viscosity.