Separation of Phytosterol Oxidation Products in Vegetable Oils by Column Chromatography

One of the most important steps to determine phytosterol oxidation products (POPs) in foods is their enrichment and purification with different methods before GC or GC-MS analysis. In this study, a new SPE method (1 g, silica) was developed to enrich and separate POPs from transesterified oils. This method showed high recovery (88- 96%) for oxidation products. New method was applied to olive, hazelnut and corn oils. Eleven oxidation products were characterized which corn oil had the highest amount (24 ppm). Among oxidation products in oils, 6β-hydroxysitostanol and 6β-hydroxycampestanol had the highest amounts. This new method had high sample capacity (up to 1 g oil) and could be also applied for food products with high phytosterol content. The new method developed in this study was simple and rapid, which simplifies separation and enrichment of POPs for further analysis by GC and GC-MS.