Characterization of the carbonyl compounds in reverted soybean oil1,2,3

Twenty-one mono-carbonyl compounds were identified in a reverted but not rancid soybean oil with a peroxide number of 2.7 meq/kg and a flavor score of 6.0. Six of the carbonyl compounds were saturated methyl ketones, ten were saturated aldehydes and five were 2-enals. The amount of 2,4-dienals in the reverted soybean oil was too small to be fractionated and identified. One fraction of the 2,4-dinitrophenylhydrazones of mono-carbonyl compounds obtained was different in chemical properties from those of the four known classes of compounds; viz. saturated aldehydes, saturated ketones, 2-enals, and 2,4-dienals. The chemical identity of this fraction has not been completely established.