|KNOWLTON, S - I.E. DU PONT DE NEMOURS
Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/7/1997
Publication Date: N/A
Interpretive Summary: Plant breeders have developed new types of oilseed plants based on soybean or rapeseed that have been improved by changing the composition of the oil fraction resulting in oils known as low linolenic soybean oil or high oleic canola oil. These new oils need to be evaluated for use as food oils. A new corn oil having altered composition to increase the oleic acid content from that of regular corn was evaluated for frying stability. In frying tests, we have determined that high oleic corn oil had longer frying life than regular corn oil or hydrogenated corn oil. French fried potatoes prepared in the high oleic corn oil had fried food flavor quality equal to that of potatoes fried in hydrogenated corn oil. These results indicate that oleic corn oil provides a high-stability, good- quality corn oil (as a frying oil) for food manufacturers.
Technical Abstract: To determine the frying stability of corn oils genetically modified 65% oleic acid, dry and wet milled high oleic corn oils were evaluated in room odor tests and by total polar compound analysis. Flavor characteristics of french fried potatoes prepared in the oils were also evaluated by trained analytical sensory panelists. In comparison to normal corn oil, hydrogenated corn oil and high oleic (80 and 90%) sunflower oils, the high oleic corn oils had significantly lower total polar compound levels after 20 hours of oil heating and frying at 190 deg than the other oils. Fried food flavor intensity was significantly higher in the normal oil during the early portion of the frying schedule than in any of the high oleic or hydrogenated oils; however, after 17.5 hours of frying, the potatoes fried in normal corn oil had the lowest intensity of fried food flavor. Corn oil also had the highest intensities of off-odors including acrid and burnt in room odor tests. High oleic corn oil was also evaluated as a salad oil for flavor characteristics and oxidative stability. Results showed that dry milled high oleic corn oil had good initial flavor quality and was significantly more stable than the normal corn oil after oven storage tests at 60 deg as evaluated by peroxide values and flavor scores.