Author/Authors :
Moulodi، F نويسنده Department of Hygiene and Food Safety, Faculty of Health, Qazvin University of Medical Sciences, Qazvin, Iran , , Qajarbeigi، P نويسنده Department of Hygiene and Food Safety, Faculty of Health, Qazvin University of Medical Sciences, Qazvin, Iran , , Rahmani، K نويسنده Department of Chemistry, Mahabad Branch, Islamic Azad University, Mahabad, Iran , , Haj Hosseini Babaei، A نويسنده Department of Chemical Engineering, Faculty of Chemical Engineering, Zanjan University, Zanjan, Iran , , Mohammadpoorasl، A نويسنده Department of Hygiene and Food Safety, Faculty of Health, Qazvin University of Medical Sciences, Qazvin, Iran ,
Abstract :
Background: Fatty acids are the main compounds in edible oils. Oil thermal stability depends on the composition of fatty acids. So, this study was conducted to investigate the effect of fatty acid composition on the oxidative stability of extra virgin olive oil dur-ing heating process.
Methods: Totally, eight virgin olive oil samples, including five imported oils from mar-ket place of Mahabad and three local ones from Qazvin were analyzed to evaluate their thermal stability. Samples were heated at 120 °C for 4 h. Sampling was carried out in 2 h intervals, then fatty acid composition, peroxide, anisidine and totox values were assessed according to Iran national standards. All determinations were carried out in triplicates, and data were subjected to analysis of compare means (t test) and spearman correlation coefficients using SPSS 16.0.
Results: Results show that there is a significant correlation between palmitoleic acid and totox index in 2 h (r=0.786) and 4 h (r=0.762), and the same result is observed between linoleic and totox index in 2 h (r=0.643) and 4 h (r=0.786). But, there is an inverse rela-tionship between oleic acid and totox index in 4 h (r=-0.833).
Conclusion: Results indicated that linoleic acid and palmitoleic acid have a reducing ef-fect on thermal stability of extra virgin olive oil in 2 h, but oleic acid increases it in 4 h.
