Document Type: Original research
Nutrition and Food Sciences Research Center, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
Department of Food Science &amp; Technology, Safadasht Branch, Islamic Azad University, Tehran, Iran
The aim of this study is to evaluate the effects of thermal processing of virgin olive oil, canola and frying oil on chemical oxidative indices (peroxide, p-anisidin value and oxidative stability), acid value and fatty acid compositions. The oil samples were exposed to heat treatment at 180 °C and qualitative parameters were determined at 0, 60, and 90 min after thermal processing. The results indicated that the parameters of acidity, p-anisidin value increased over time (P <0.05). Oxidative stability at 110 °C was also analyzed using Rancimat. Resistance to oxidation in frying and canola oils reduced(P <0.05) faster than that in virgin olive oil due to presence of sterolic compounds with antioxidant properties in olive oil that is activated at high temperatures and increases stability of olive oil. Therefore, the virgin olive oil regarding to its nutritional properties, being rich in oleic acid (67%) and containing natural antioxidant compounds might be a good choice to be in the basket of goods of families for domestic frying.