Oxidative and thermal stabilities of genetically modified high oleic sunflower oil

The oxidative and thermal stabilities of genetically modified high oleic sunflower oil (87% oleic acid) were compared with those of regular sunflower (17% oleic acid), soybean, corn, and peanut oils during storage at 55 °C and simulated deep fat frying at 185 °C. Oxidative stability was evaluated by measuring the oxygen content and volatile compounds in the sample bottle headspace and peroxide value. The coefficient variations (CVs) for volatile compound, headspace oxygen, and peroxide value analyses were 2.02%, 1.41%, and 3.18%, respectively. The oxidative stability of high oleic sunflower oil was greater than those of regular sunflower and soybean oil (P < 0.05) and as good as those of corn and peanut oils (P > 0.05). The thermal stabilities of oils during deep fat frying were evaluated by measuring the infrared absorption at 2.9 μm and conjugated diene content. The CV of conjugated diene content was 1.07%. Infrared and conjugated diene results showed that the high oleic sunflower oil had greater thermal stability than had regular sunflower, soybean, corn, and peanut oils (P < 0.05). The genetically modified high oleic sunflower oil, with 5.5% linoleic acid, had better oxidative and thermal stabilities than had the regular sunflower oil with 71.6% linoleic acid.