Frying quality and oxidative stability of high‐oleic corn oils

Abstract

AbstractTo determine the frying stability of corn oils that are genetically modified to contain 65% oleic acid, high‐oleic corn oil was evaluated in room odor tests and by total polar compound analysis. Flavor characteristics of french‐fried potatoes, prepared in the oil, 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, high‐oleic corn oil had significantly (P<0.05) lower total polar compound levels after 20 h of oil heating and frying at 190°C than the other oils. Fried‐food flavor intensity was significantly higher in the normal corn oil during the early portion of the frying schedule than in any of the high‐oleic or hydrogenated oils; however, after 17.5 h 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 also was 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 (P<0.05) more stable than dry‐milled normal corn oil after oven storage tests at 60°C, as evaluated by flavor scores and peroxide values. Although the high‐oleic corn oil had significantly (P<0.05) better flavor and oxidative stability than corn oil after aging at 60°C, even more pronounced effects were found in high‐temperature frying tests, suggesting the advantages of high‐oleic corn oil compared to normal or hydrogenated corn oils.