On the Participation of Fatty Alcohols in Inhibited Oxidation of Lipids

The effect of 1‐tetradecanol and 1‐octadecanol in concentration of (0.5‐9.0)·10 −2 mol/l on the hydroquinone (1.10 −4 mol/l)‐inhibited oxidation of the triacylglycerols of sunflower and olive oils at 80° and 110°C has been investigated along with the role of temperature changes within the range 23°‐100°C. It is established that fatty alcohols accelerate the inhibited oxidation of lipids by participating in (i) the blocking of the phenolic antioxidant through the formation of a hydrogen bond‐based complex and (ii) the proceeding of additional reactions such as chain propagation, chain branching and chain termination. The alcohol with a shorter chain length leads to the formation of a complex where the bond with the inhibitor is stronger whereas the alcohol with a longer chain length exhibits a higher activity in the elementary reactions of propagation, branching and termination of chains. The type of the lipid substrate is found to cause no qualitative change of the effect of alcohols. It is established that with increasing unsaturation (oxidizability) degree of the lipid substrate the effect of fatty alcohols on the inhibitor efficiency and the rate of inhibiting oxidation increase. The change of temperature has a specific effect on the contribution of the two alcohols to the decrease of the inhibitor efficiency and the increase in the rate of the inhibited process.