ROLE OF LIPOXYGENASE AND LIPID OXIDATION IN QUALITY OF OILSEEDS

Lipoxygenase is a prime suspect for catalyzing lipid oxidation in raw peanuts but it is destroyed in the roasting process. After roasting, however, lipid oxidation is catalyzed primarily by nonenzymic catalysts. Examination of several fresh samples of commercial peanut butters showed that the initial peroxide contents differed. This suggested that the samples were already in different stages of peroxidation and demonstrated the need for controlling oxidation in the peanuts before roasting and processing. We found that minor constituents such as metals, metalloproteins, and salts are possible catalysts of lipid oxidation. When ascorbyl palmitate, citric acid, or ethylenediaminetetraacetic acid were added to the peanut butter before storing, oxidation was decreased or completely controlled. Some natural compounds were also examined as possible inhibitors of lipoxygenase activity in raw peanuts. © 1979, American Chemical Society. All rights reserved.