Chicken fat is fat obtained (usually as a by-product) from chicken rendering and processing. Of animal-sourced substances, chicken fat is noted for being high in linoleic acid, an omega-6 fatty acid. Linoleic acid levels are between 17.9% and 22.8%. It is a common flavoring, additive or main component of chicken soup. It is often used in pet foods, and has been used in the production of biodiesel. Chicken fat is one of two types of animal fat referred to as schmaltz, the other being goose fat.