n‐deca‐2,4‐dienal, its origin from linoleate and flavor significance in fats

Abstract
Summary: n‐Deca‐2,4‐dienal was identified as a major component of the carbonyl compounds in deodorization distillates from cottonseed oil, soybean oil, beef tallow, and lard. This compound also was demonstrated as a principal carbonyl component in the heat decomposition of methyl linoleate in the presence of moisture. n‐Hept‐2‐enal and C10 and C9 2‐enals also were detected in the latter system. The flavor threshold of decadienal in water was found to be approximately 0.5 parts per billion. Flavor and odor qualities of the dienal perhaps are described best by the term “deepfried.” The compound's significance in fried and baked foods and its performance in the Kreis and 2‐thiobarbituric acid tests for fat oxidation are discussed.