Grape seed extract inhibits lipid oxidation in muscle from different species during refrigerated and frozen storage and oxidation catalyzed by peroxynitrite and iron/ascorbate in a pyrogallol red model system

The antioxidant effect of grape seed extract (GSE) was determined by assessing the bleaching of pyrogallol red (PGR) by peroxynitrite or iron/ascorbate, and the formation of lipid hydroperoxides (LOOH) and thiobarbituric acid substances (TBARS) in raw or cooked ground muscle during refrigerated or frozen storage. In PGR models, GSE was more effective than gallic acid in inhibiting oxidation. The formation of LOOH and TBARS was inhibited by GSE (0.1% and 1.0%) compared to untreated controls and samples treated with sodium tripolyphosphate. Diethylenetriaminepentaacetic acid (DTPA), alone or in combination with GSE, had no effect on LOOH or TBARS, which provides clues about the possible mechanism of action of GSE. These results show that GSE at concentrations as low as 0.1% is a very effective inhibitor of primary and secondary oxidation products in various muscle systems and has potential as a natural antioxidant in raw and cooked meat systems. (C) 2007 Elsevier Ltd. All rights reserved.