Cholesterol oxides in processed meats.

Methods for the extraction of cholesterol oxides from meats were studied. A dry column technique for the extraction of sterols was found to be more rapid and convenient than conventional chloroform-methanol extraction. An overall yield of 32·0% and 23·6% for radiolabelled cholesterol and cholesterol oxides, respectively, was obtained after dry column extraction, saponification and chromatography on a silica arrestant column, Florisil®-AgNO(3) column and silica Sep-Pak® column. The overall extraction efficiency of ten meat samples was 22·3 ± 1·7 %. Cholesterol oxides present in measurable amounts included 5-cholesten-3β, 19-diol, 5-cholesten-3β-ol-22-one, the α and β epimers of 5-cholesten-3β, 7-diol and cholestan-3 β, 5α, 6β-triol in some of the meat samples analyzed, but, for the majority of samples, no detectable amounts of known cholesterol oxides were found. Most of the meats, however, contained unidentified components that are non-polar with respect to cholesterol.