Corn oil is oil extracted from the germ of corn (maize) Its main use is in cooking, where its high smoke point makes it a valuable frying oil. It is also a key ingredient in some margarine. One metric ton of corn contains 28 kg of corn oil (2.8% by weight). Refind corn oil is 99% triglyceride, with proportions of approximately 59% polyunsaturated fatty acid, 24% monounsaturated fatty acid and 13% saturated fatty acid. Corn oil is also one source of biodiesel. Other industrial uses for corn oil include soap, salve, paint, rust proofing for metal surfaces, inks, textiles, and insecticides. It is sometimes used as a carrier for drug molecules in pharmaceutical preparations.