Some carbonyl flavor compounds of oxidized soybean and linseed oils

Evidence is presented that 2,3-pentanedione, as well as diacetyl, contributes to the buttery flavor found in the early stages of oxidation of soybean oil. Components with a fishy and potatoey flavor were found in distillates from soybean oil that had a fishy or paint-like flavor. Linseed oil proved a reliable source of these flavor compounds. The fishy compound was identified ascis-4-heptenal and the potatoey compound is probably 2,4-pentadienal. Mechanisms for the production of these compounds are suggested. Journal Paper No. J-6183 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa, Project No. 1517.