Changes of antioxidants (sesamol, sesaminol and tocopherol) and a precursor of antioxidant, sesamolin, in two types of sesame oil during frying processes with or without frying materials were investigated.
In the roasted seed oil, a type of oils, the production of sesamol from sesamolin during frying processes occurred in both frying tests with or without frying materials. But with some frying materials, the amount of sesamol produced was rather lower than without materials. The amount of tocopherol did not decrease during frying (180± 5°C, 45 min) with or without frying materials. In case of potato sticks' frying, sesamolin was hydrolyzed to sesamol and samin. In the unroasted seed oil, another type of oil, main antioxidant, sesaminol was found to be stable during frying temperatures with or without frying materials. The amount of tocopherol did not change, too.
Thus, it is thought that both type of sesame oils were very suitable for frying, because of protective action against the thermal oxidation of antioxidants contained in the oils.