Antioxidative activity of spices and spice extracts.
1997
Madsen H.L. | Bertelsen G. | Skibsted L.H.
The antioxidative activity of spices and spice extracts can usually be traced beck to their content of phenolic compounds. Plant phenols may scavenge free radicals involved in lipid peroxidation as has been documented in several model systems, although other mechanisms should be considered especially in relation to the early stages of oxidative deterioration. Phenolic compounds isolated from spices have been found to react with hydroxyl radicals with nearly diffusion controlled reaction rates. An assay based on a combination of determination of phenol equivalents and determination of radical scavenging capacity by the ESR spin trapping technique confirms the nearly diffusion controlled reaction rates and may prove useful for exploration of new plant materials and for adjustment of extraction procedures, including selection of solvent. This and other assays based on oxygen depletion measurements are recommended prior to final testing in real foods. Co-extracted chlorophylls in spice extract present a problem as photosensitizers in food exposed to light during storage and use.
显示更多 [+] 显示较少 [-]