The synergistic antioxidant effects of d-tocopherol (Toc) and several spicy compounds on lard and plam oil were investigated by oven and AOM tests. The antioxidant effects of spicy compounds were also studied in the same manner.
1) By the oven test, cinnamaldehyde, capsaicine and thymol showed weak antioxidant effect on lard, but spicy compounds which enhanced the antioxidant effect of Toc were capsaicine, cineol, camphene, phellandrene and geraniol. However, no effect was observed on palm oil.
2) By the AOM test, only capsaicine showed antioxidant effect on lard, but none of the spicy compounds enhanced this effect of Toc.
3) Remnant ratios of the spicy compounds after a month of the oven test were lower than 30%, except in the case of capsicine which may possibly volatilize after such a period of time. However, the ratios of capsaicine and thymol which had antioxidant effects were higher than those of other compounds on lard. The remnant ratio of total Toc in lard increased by the addition of capsaicine, cineol, camphene, phellandrene or geraniol, indicating these compounds to possibly protect Toc from oxidative decomposition.
