Description
Corn oil (Maize oil) is oil extracted from the germ of corn
(maize). 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.[citation needed] One bushel of corn contains 1.*5 pounds of
corn oil (2.8% by weight). Corn agronomists have developed high-oil
varieties; however, these varieties tend to show lower field
yields, so they are not universally accepted by growers.Corn oil is
also a feedstock used for biodiesel. Other industrial uses for corn
oil include soap, salve, paint, rustproofing for metal surfaces,
inks, textiles, nitroglycerin, and insecticides. It is sometimes
used as a carrier for drug molecules in pharmaceutical
preparations.
Almost all corn oil is expeller pressed, then solvent extracted
using hexane or isohexane
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 (bleaching). Final steps in refining include
winterization the removal of waxes), and deodorization by steam
distillation of the oil at **2 - **0C (**0 - **0F) under a high
vacuum.
Some specialty oil producers manufacture unrefined, **0% 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 smaller market share.