Abstract
The synergistic antioxidant effects of tocopherols (Tocs) and extracted components from clove on lard and palm oil were investigated by oven and AOM tests. From the components obtained, powdered commercial clove was extracted with petroleum ether (PE) and ethanol (EtOH) followed by fractionation of the EtOH extract through solubilization in hexane and silica-column chromatography. The antioxidant effects of them were also studied in the same manner.
1) Both of PE and EtOH extracts of clove clearly showed antioxidant effects on lard by addition at 0.2%, the effect of the latter being stronger.
2) The hexane soluble component above the EtOH extract also showed antioxidant effect, and somewhat enhanced the effect of a mixture of d-Toc (m-Toc) on lard. The insoluble component enhanced synergistically the effect of m-Toc by hindering increase in POV during the induction period.
3) Such effects as those of the above soluble component were observed at 500ppm or more of eugenol, the main effective constituent of clove a spice. However, at 100ppm with the addition of acetyl eugenol, and analogous constituent, no effect was observed.
4) No extracted component of clove such an inhibitory effect on the oxidation of palm oil.