Title: Studies to Determine the Nature of the Damage to the Nutritive Value of Some Vegetable Oils from Heat Treatment IV. Ethyl Esters of Heat-Polymerized Linseed, Soybean and Sunflower Seed Oils
Abstract: The non-adduct-forming fraction (NAFD) of the distillable esters from heated soybean oil was toxic, though to a lesser degree than that from the comparable fraction obtained from linseed oil. The NAFD from heated sunflower seed oil, however, was only slightly injurious to the rats. The adduct-forming fractions from both the heated soybean oil and the heated sunflower seed oil were nutritionally harmless. The chief chemical difference between the NAFD fractions from the three heated oils was in respect to their behaviour on alkali isomerization. The NAFD from heated linseed oil displayed relatively little increase of its absorbance at 233 mμ, whereas the results for the soybean and sunflower seed oils suggested the presence of high proportions of difficultly conjugable diene unsaturation. These results suggest that the non-adduct-forming fraction of the distillable esters of heated linseed may contain a high proportion of non-conjugable diene cis-isomers, possibly of cyclic structure.