An attempt was made to compare the antioxidant activity of ethanol extracts of a glucose-ammonia (0.2 M+0.2 M) browning mixture with that of the corresponding glucose-glycine mixture, in soybean oil substrates, on the basis of peroxide value (POV), thiobarbituric acid value (TBA-value) and acid value (AV) development.
Absorbances, at 470 ㎚, of the former mixture after 2 and 5 hour browning were 1.88 and 3.42 while those of the latter mixture were 0.02 and 0.07. The POVs of the supstrates containing the extracts taken after 2, 15, and 40 hrs from the former
mixture were 15.8. 14.2, and 12.6 after 30 day storage at 42.3±2.6 ℃. Those of the latter mixture were 17.4, 16.1, and that of the control was 82.1. TBA and acid value development followed similar trends.
These results indicated that the antioxidant activity of the extracts of the glucose-ammonia mixture was slightly stronger than that of the glucose-glycine mixture. They also suggested that effective antioxidants had already been formed in the earlier stages of the glucose-anmonia mixture, and that brown-pigments formed did not contribute significantly to the activity of the mixture.
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