Effect of Ingested Thermally Oxidized Corn Oil on Fat Composition in the Rat

Abstract

Five groups of weanling rats were kept for 59 days in individual cages and fed adequate diets which contained 2% cottonseed oil and 10% of the following fats: (1) corn oil, (2) oxidized corn oil, (3) hydrogenated oxidized corn oil, (4) fatty acids from oxidized corn oil, and (5) 10% oxidized fatty acids plus 90% fresh fatty acids from corn oil. All animals were restricted to the same amount of daily food intake as those fed fresh corn oil and samples of feces were collected for lipid analysis. At the end of the test period the animals were sacrificed; the carcass lipids were extracted, converted to methyl esters and subjected to gas lipid chromatographic analysis. The results indicated that hydroxy acids, originating from oxidized fats, were deposited and influenced the character of the normal mixed fatty acid composition of the carcass fat. The lipids of rats fed oxidized fats contained from 4-7% hydroxy acids, levels similar to those previously observed in rats fed ricinoleic acid or triricinolein.