OCCURRENCE AND FORMATION OF BITTER-TASTING TRIHYDROXY FATTY-ACIDS IN SOYBEANS

A quantitative method for the determination of the mixture of 9, 12, 13-trihydroxyoctadeca-10-enoic acid and 9, 10, 13-trihydroxyoctadeca-ll-enoic acid (Tri-OH) in legumes is reported. Storage of a soybean flour at 22 °C increased the Tri-OH content from 0.03 to 0.05% in 3 months. Components of soybeans, glutathione, and horse radish peroxidase (HRP) were tested for their ability to form Tri-OH from linoleic acid hydroperoxides. Most effective was a protein fraction from soybeans containing lipoxygenase and peroxidase activities, followed by HRP and by proteins. In the latter case thiol groups are involved in the Tri-OH formation. © 1979, American Chemical Society. All rights reserved.