Submitted to: Journal of Cereal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 24, 1996
Publication Date: N/A
Interpretive Summary: Oat has the highest oil concentration of the cereals. By selecting for high oil over a series of generations, plant breeders obtained strains with oil concentrations as high as 18%. It was suggested that oat with oil this high could economically be grown and processed as an oil crop. Also, high-oil oat has more energy as animal feed. This study was performed to determine certain characteristics of these high-oil oat strains that might relate to their value for processing or feed. We found that protein concentration was higher in the high-oil oat, suggesting the possibility that the by-product of oil extraction would be valuable as a feedstuff or food ingredient. Also, vitamin E increased with increasing oil concentration. This could be important for stability of the oil, and vitamin E is beneficial to humans as an antioxidant. Microscope studies showed that the density of protein and oil droplets increased throughout the grain as oil concentration increased; these components were not concentrated in certain parts. This finding has implications for the methods of processing. Further work on the processing characteristics of high-oil oat is indicated.
Technical Abstract: Oat(Avena sativa L.) selections, with elevated oil concentrations ranging from 6.9 to 18.1 percent, were obtained from a recurrent breeding regime at Iowa State University. These selections, along with two check cultivars, were analyzed to determine their tocol (tocopherols and tocotrienols), protein, starch and beta-glucan concentrations. Kernels were also examined dby histochemical techniques to locate all the oil bodies, protein bodies, and beta-glucan. Tocotrienol concentration was correlated with oil concentration (R2=0.83), but tocopherol concentration was not. Tocotrienols are predominantly located in the endosperm, whereas tocopherols are concentrated in the germ. Protein and beta-glucan concentrations also increased with increasing oil concentration. The data indicate that high-oil oat can be an important source of tocotrienols, which are extracted with the oil. Tocotrienols are antioxidants and have cholesterol-lowering properties in humans and experimental animals. The residue after oil extraction contains high concentrations of protein and fiber, and could be fractionated into useful food components.