Direct determination of<i>trans</i> unsaturation in triglycerides by infrared spectrophotometry

Abstract A differential infrared spectrophotometric method is described for the determination of trans unsaturation in fats. The method utilizes absorption at 965 cm 蜢1 , due to the C蜢H out‐of‐plane deformation vibrations of trans unsaturated compounds. The method is rapid, accurate, and directly applicable to the determination of trans unsaturation in triglycerides. It is applicable to samples which contain low concentrations of trans acids (down to 2%) and also to samples with fatty acids of mixed chain length.