Synthetic and natural antioxidant additives in food stabilization: current applications and future research - Oxidation in Foods and Beverages and Antioxidant Applications - page 282

Fig. 12.6 Chemical structure of ascorbyl palmitate.
acid moiety. The ester functions as an oxygen scavenger and a synergist, just
like free ascorbic acid. It is, therefore, no surprise that the ester acts syner-
gistically with tocopherols to regenerate them after they have been oxidized to
tocopheryl radicals. Combinations of ascorbyl palmitate with tocopherols,
lecithin, PG, and TDPA, have been used to stabilize animal fats (Cort, 1974;
Park and Addis, 1986), vegetable oils (Cort, 1974) and frying fats (Gwo et al.,
1985).
12.4.6 Ethoxyquin
Ethoxyquin (EQ; 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline) (Fig. 12.7) is a
synthetic antioxidant used widely in the feed industry and as a stabilizer for
carotenoids, fish meal, and ground paprika. It forms a stable nitroxide free
radical upon oxidation, which is a more effective antioxidant than EQ itself (Lin
and Olcott, 1975; Weil et al., 1968). For a more thorough discussion on the
mechanism of action of ethoxyquin, and its relationship to hindered amine light
stabilizers, see Section 12.6.4.
Fig. 12.7 Chemical structure of ethoxyquin.