Bleaching of vegetable oils: I. Conversions in soybean oil, triolein and trilinolein

Soybean oil, triolein and trilinolein were treated with acid‐activated earth (2–15%) at 25–120 C. With low initial peroxides and in the absence of air, little additional conjugation was found. With high initial peroxides or in the presence of air, conjugated dienes and trienes were formed particularly with high amounts of earth. At higher temperatures and longer bleaching times the amount of conjugated compounds also increased. It can be concluded from the bleaching experiments with triolein and trilinolein that conjugated dienes, trienes and tetraenes are formed much more easily with linoleate than with oleate.