In previous papers, the authors, members of the Fat Stability Committee of Japan Oil Chemists' Society, reported the results of fat stability tests on autoxidation.
The present paper presents the results of collavorative tests on fat thermal oxidative stability. Oils were heated at 180°C or 200°C in an AOM Test Tube. Carbonyl, anisidine and acid values and viscosity of the heated oils were measured. The carbonyl value (fresh soybean oil, about 2) increased linearly to about 15 after 10h heating at 200°C. That of anisidine value (fresh corn oil, about 5) increased to about 180 after 20h of heating at 200°C. The acid value and viscosity of the heated oils (10 or 20h heating at 180 or 200°C) increased only slightly.
