The antioxidant activity of low-molecular weight Mailard reaction products, 2.5-dimethy1-4-hydroxy-3(2H)-furanone (DMHF), 2,4,5-Trimethyloxazole, 2,4,5-trimethythiazole, 2,3,5-trimethylpyrazine, furan, furfural, pyrrole, imdazole, and tutylated hydroxytoluene (BHT) was examined by means of the peroxide value (POV) and carbony1 value (COV) development of refined soybean oil substrates containing 0.01 M of each compound and a control. The control and oil substrates were autoxidized at 40℃. The antioxidant activities of the compounds and BHT based on the POVs of the control and substrates after 18 day´s oxidation decreased in the order as folows: BHT>imidazole>>pyrrole>>DMHF>2,3,5-trimethylpyrazine >furan>furfural. The
antioxidant activity of pyrrole was weaker than those of BHT and imidazole. The difference was significant at 1% level. Imidazole and pyrrole demonstrated stronger activities than DMHF, 2,3,5-trimethylpyrazine, furan, and furfural.. The difference was also significant at the same level. The differences of the activities among the latter group were insignificant at 1% level. 2,4,5-Trimethyloxazole and 2,4,5-trimethylthiazole seemed to possess weak prooxidant activities. The prooxidant activities, howerer, were not meaningful at 1% level. The results of the COV determination supported those of
the POV determination well.
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