ARS | Publication request: Corn kernel oil and corn fiber oil

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: December 13, 2008
Publication Date: May 1, 2009
Citation: Moreau, R.A., Singh, V., Powell, M.J., Hicks, K.B. 2009. Corn kernel oil and corn fiber oil. Book Chapter in "Gourmet and Health-Promoting Specialty Oils", ed. by R. A. Moreau and A. Kamal-Eldin, AOCS Press, Urbana, pp. 409-431.

Technical Abstract: Unlike most edible plant oils that are obtained directly from oil-rich seeds by either pressing or solvent extraction, corn seeds (kernels) have low levels of oil (4%) and commercial corn oil is obtained from the corn germ (embryo) which is an oil-rich portion of the kernel. Commercial corn oil could actually be called “corn germ oil.” Although it has long been known that oil could be obtained directly by extracting it from ground corn, the low levels of oil in most corn kernels (~4%) have been an indication that obtaining corn oil directly from corn kernels may not be economical. However, if the corn oil extraction process could be linked to a second profitable process, then the economics of corn kernel oil production might be favorable. Recently our laboratory has demonstrated that corn kernel oil has health-promoting properties because of its very high levels of lutein and zeaxanthin (valuable for preventing macular degeneration) and its moderate levels of tocopherols, tocotrienols, and phytosterols. Corn Fiber Oil was first developed in our laboratory in the mid-1990s. We reported that the chemical composition of corn fiber oil, obtained by extracting wet milled corn fiber with either hexane or supercritical CO2, was very different than that of commercial corn oil. Whereas, commercial corn oil contains about 1% phytosterols (plant sterols), corn fiber oil contains 10-15% phytosterols. During the 1990s there was much international interest in phytosterols because of several clinical studies that had demonstrated that eating 1-2 grams per day of phytosterols could reduce the levels of cholesterol in the blood by 10-15%. Because of its very high levels of phytosterols one could obtain the 1-2 grams per day of dietary phytosterols required to effectively lower serum cholesterol, by consuming 10-20 grams (1-2 tablespoons) of corn fiber oil.