How Corn Oil Is Made: Production, Extraction, and Refining Process

Corn oil is produced in essentially the same way as other vegetable fats: the corn germ is cleaned of impurities and crushed on roller mills before further processing.

After crushing, the corn germ is roasted and given a preliminary pressing. The cake that still contains oil is then pressed a second time or, as is now more commonly the practice, the fat is extracted from the cake using benzine.

Crude corn oil obtained after pressing and extraction is dark in colour and has an unpleasant taste, making it unsuitable for food in that state. A method of deep purification — refining — of corn oil was developed by the All-Union Scientific Research Institute of Fats together with the Central Scientific Research Institute of the Starch and Syrup Industry.

Once refined, corn oil is fully ready for consumption, or it can be hydrogenated and used in the manufacture of margarine. In its properties, refined corn oil is very close to sunflower oil, but it has a more pleasant taste. It is a yellow-golden oil with a specific gravity of 0.924–0.926.

Corn oil solidifies at a temperature of around 10 °C. Its main value lies in the fact that it contains about 85% unsaturated fatty acids and is rich in vitamin E (tocopherol). A separate article covers the benefits of corn oil.