Critical kinetic transition points over the vegetable oils peroxidation monitored simultaneously by peroxide and carbonyl values

To ascertain the cut-off peroxide (PV) and carbonyl (CV) values for the rejection of oleic, oleic-linoleic, and linolenic groups of vegetable oils, kinetics of change in the PV and CV of olive, corn, sesame, and canola oils were studied during an accelerated storage at 45 °C. Increases in PV and CV followed successive linear and sigmoidal kinetic models (R 2 > 0.95 and RMSE < 0.85) over the initiation and propagation, respectively, phases of lipid peroxidation. The kinetic transition points in the propagation phase were used to introduce the cut-off PVs and CVs for rejection purposes. Naturally, the oil groups of inherently lower oxidative stability possessed the cut-off values which their coordinates were closer to those of the onset of the phase. The potential cut-off PVs to reject the canola, corn, sesame, and olive oils were determined to be about 7.0, 7.5, 19, and 30 mEq O 2 /kg oil, respectively. The cut-off CVs of about 5.0, 5.5, 6.0, and 7.0 µmol 2,4-decadienal/g oil were determined to reject the sesame, canola, corn, and olive oils, respectively.