ABSTRACT
The effect of the antioxidant Ronoxan A and of two of its components (ascorbyl palmitate, lecithin) and of tocopheryl acetate was tested for the stabilization of fats and retinyl acetate. In the present study, results obtained in sunflower oil, soybean oil, milk fat and in the mixtures of these fats in concentrations corresponding to their levels in the Czechoslovak Infant Formula (Feminar) are compiled. The antioxidant levels applied, i.e. those used in Czechoslovakia for the stabilization and enrichment of vegetable oils and Feminar, have a protective effect on retinyl acetate to a certain extent as well, and in no case they affect it unfavourably. All antioxidant combinations applied cause a significant retardation of the fat autoxidation. Ronoxan A has the best effect in all cases tested.
Subject(s)
Antioxidants , Ascorbic Acid/analogs & derivatives , Dietary Fats , Infant Food , Lipids , Phosphatidylcholines , Vitamin A , alpha-Tocopherol/analogs & derivatives , Animals , Cattle , Drug Combinations , Drug Stability , Humans , Infant , Milk , Oils , Tocopherols , Vitamin E/analogs & derivativesABSTRACT
Oxidation and oligomeric products of sunflower oil were determined by gel permeation chromatography after transformation into methyl esters and prefractionation by urea. During oil refining the content of oxidation monomeric products increased from 0.9% to 1.5%, the dimer content from 0.06% to 0.32%, and the trimer content from 0.02% to 0.10%. During hydrogenation the content of polar monomeric oxidation products decreased to 0.9%, the dimer content to 0.28% and that of trimers to 0.03%. Oligomers were partly adsorbed on the surface of catalyst and carrier, because fat isolated from the catalyst contained more than 3% of oligomers. The content of oligomers established in the refined sunflower oil and in the hydrogenated sunflower oil produced on an industrial scale was lower than values given as limiting with respect to hygiene safety, sensory value and stability against oxidative rancidity.
Subject(s)
Oils , Chromatography, Gel , Esters , Food Handling , Oxidation-Reduction , UreaABSTRACT
Olive oil was converted into methyl esters which were autoxidized at 60 degrees C. The composition of oxidized products was determined by the comparison of infrared spectra and NMR spectra of the original and acetylated samples, the sample reduced with potassium iodide and the acetylated reduced sample. Oxidized products were separated by preparative thin layer chromatography on silica gel and characterized by selective detection and by infrared spectrometry of the fractions. The oxidation products consisted of hydroperoxido butyl oleate, substituted hydroperoxides, mono- and disubstituted monomeric derivatives and a small amount of oligomers.
