Effect of wood carbohydrates on the oxidation of unsaturated fatty acids

•Impregnating oils for wood protection.•Effect of carbohydrates on oxidation of vegetable oils.•Chemical interaction during oxidation.•Oxidation of methyl linoleate studied using FT-IR.

The aim of this study is to better understand the oxidation mechanism of the fatty acids applied on wood surfaces. In the present study, model hemicellulose compounds were used to measure the effect of polysaccharides on auto-oxidation of methyl linoleate utilizing infrared spectroscopy (RT-IR). The auto-oxidation process of methyl linoleate was measured in combination with 1 wt% reducing and non-reducing hemicellulose model compounds (HMC) at 70 °C. The effect of HMC on the methyl linoleate auto-oxidation process was also compared with the effects of glycerol and glyceraldehyde, using same analytical method and reaction conditions. The IR-spectra of methyl linoleate with 1 wt% carbohydrates before and after oxidation were analyzed and peak intensity variations during oxidation in the region of 3010 cm−1, 990 cm−1, and 970 cm−1 were calculated during oxidation process. It was observed that lactose and sucrose accelerated the radical reactions; however, glycerol has an anti-oxidative effect on the fatty acids oxidation. An interaction mechanism for these findings is proposed and discussed.