Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/5/2002
Publication Date: 8/5/2002
Citation: Cereal Chemistry 80(2):p.123-125 (2003) Interpretive Summary: Corn fiber oil (CFO) is a potentially high valued co-product that can be recovered from corn fiber. Corn fiber oil contains some unique compounds that have cholesterol-lowering properties. The extraction of corn fiber oil is very expensive because there is only 1.5 to 3.0% oil in the fiber. Corn coarse fiber is comprised of two major layers of cellular material, the outer pericarp (which makes up about 60% of the coarse fiber) and the inner aleurone cell layer (which makes up the remaining 40%). Recently we showed that most of the corn fiber oil and its cholesterol lowering compounds are located in the aleurone layer. In this study an effort was made to develop a process to purify aleurone layer cells from corn fiber. The results showed that a small amount of "aleurone cell-enriched" fraction could be recovered in the "floated" fraction, obtained by grinding the fiber, mixing it with water, and allowing the mixture to settle or float. Although the process needs additional refinement before it can be a commercial success, this study confirmed our hypothesis that development of an economical process to purify corn aleurone will very likely lower the cost of corn fiber oil.
Technical Abstract: Corn fiber oil contains unique compounds called phytosterols that have been shown to have nutraceutical properties. The amount of oil in corn fiber is very low, approximately 1.5 to 3.0%. Due to the low concentration of oil in corn fiber, the extraction of the oil and its phytosterol compounds is not efficient and can be expensive. Recently we showed that more than 90% of the corn fiber oil comes from the aleurone layer, which is approximately 40% of the coarse fiber fraction. If the aleurone layer can be separated from the remaining wet milled fiber fraction, it should provide an enriched source of corn fiber oil and phytosterol compounds. In this study enrichment of aleurone in the fiber fraction was done by floatation of the fiber tissue associated with the oil bodies (aleurone cells). The results showed that there is a significant enrichment of oil and individual phytosterols compounds in the fraction that was recovered by floatation, compared to the original fiber. However, the total recovery of the aleurone cells in the recovered fiber fraction was marginal.