Figure 5.

Relationships between various kinetic parameters in the peroxidation of stripped sunflower oil containing lecithin, ferulic acid, ethyl ferulate, γ-oryzanol and their combinations at 60 °C. A antioxidant activity, Et_PP end time of the termination phase or t_STP, k_f rate constant of hydroperoxides (ROOHs) formation at the propagation phase, k_d rate constant of ROOHs decomposition at the propagation phase, k₁ rate constant of the initiation phase, M_R maximum rate of ROOHs formation in the propagation phase, [ROOH]_IP ROOHs concentration at IP point, ${\left[R,O,O,H\right]}_{M_R}$ ROOHs concentration at the point of the maximum rate of ROOHs formation (or turning point), $t_{M_R}$ occurrence time of the maximum rate of ROOHs formation (or turning point), water content_IP water content at the IP point, water content_PP water content at the PP point.