Gel chromatographic separation of unsaponifiable fractions in fats and oils

Summary of available data for cholesterol in foods and methods for its determination

A search of the literature has been conducted on the cholesterol content of foods and on the methods for its determination. The amount of cholesterol in food is important because of its possible relationship to the onset of atherosclerosis in humans. Cholesterol is present primarily in foods of animal origin. The main sources in the American diet are eggs, poultry, dairy products, fish and seafood, and meat products. Only a few samples of these products have been analyzed. In many cases there is a wide range in cholesterol values for samples analyzed. Much of the research was conducted many years ago. The most commonly used methods were gravimetric or colorimetric. In many cases the samples investigated were not adequately described. Cholesterol was often determined without isolating it from interfering materials. Although some of the cholesterol values reported in the literature appear to be reasonably accurate, there is an urgent need for reinvestigation of the cholesterol content of foods using more recently developed methods of analysis.

Comparison of chromatographic methods for the analysis of glycerol esters

Column, thin-layer and gel chromatography have been compared as methods for the analysis of glycerol esters. It was found that gel chromatography gave much easier and faster analyses of monoglyceride emulsifiers, while at the same time providing a satisfactory distribution of fractions and giving an accuracy of determination corresponding to that of the standard method for their analysis.

Lipid oxidation. Part. 1. Effect of free carboxyl group on the decomposition of lipid hydroperoxide

Hydroperoxido butyl oleate was decomposed by heating in excess palmitic acid at 60-120 degrees C. The decomposition followed the kinetics of a first order reaction with formation of both monomeric and oligomeric secondary products. The proportions of oligomers slightly increased with increasing reaction temperature and decreased with increasing concentration of hydroperoxide. The activation energy was 70.4 kJ/mol +/- 4.7 kJ/mol. The decomposition of hydroperoxides proceeded partially by monomolecular cleavage, partially by formation of esters with palmitic acid.