Corn oil


Corn oil is oil extracted from the germ of corn. Its main use is in cooking, where its high smoke point makes refined corn oil a valuable frying oil. It is also a key ingredient in some margarines. Corn oil is generally less expensive than most other types of vegetable oils.
Corn oil is also a feedstock used for biodiesel. Other industrial uses for corn oil include soap, salve, paint, erasers, rustproofing for metal surfaces, inks, textiles, nitroglycerin, and insecticides. It is sometimes used as a carrier for drug molecules in pharmaceutical preparations.

Production

Almost all corn oil is expeller-pressed, then solvent-extracted using hexane or 2-methylpentane. The solvent is evaporated from the corn oil, recovered, and re-used. After extraction, the corn oil is then refined by degumming and/or alkali treatment, both of which remove phosphatides. Alkali treatment also neutralizes free fatty acids and removes color. Final steps in refining include winterization, and deodorization by steam distillation of the oil at under a high vacuum.
Some specialty oil producers manufacture unrefined, 100%-expeller-pressed corn oil. This is a more expensive product since it has a much lower yield than the combination expeller and solvent process, as well as a smaller market share.

Constituents and comparison