Effects of eliminating the triacylglycerols structure of bulk oils on
the antioxidant performance of γ-oryzanol: A kinetic and thermodynamic
study
Abstract
In this study, the effect of triacylglycerol structure on the
performance of γ-oryzanol was evaluated. For this purpose, the kinetic
parameters of pure triacylglycerols and fatty acid methyl esters of
olive, sesame, corn, sunflower, and soybean oils were calculated in the
presence γ-oryzanol at 60, 70, and 80 °C. The obtained results showed
that γ-oryzanol was more effective in improving the induction period and
the level of hydroperoxides production in fatty acid methyl ester
systems in comparison to the triacylglycerol ones. An increase in the
temperature led to higher participation of γ-oryzanol in undesirable
side reactions. The participation rate in these reactions was higher in
the higher γ-oryzanol efficiency systems. In the inhibited oxidation
reactions, eliminating the triacylglycerols structure of oils caused a
considerable increase in all Arrhenius and Eyring model parameters.
These findings revealed that the antioxidant activity of γ-oryzanol was
increased by the destruction of the triacylglycerol structure.