摘要：

A liquid chromatographic method is described for the analysis of vitamin E in margarine and vegetable oil products (spreads). The tocopherol homologs (±, , -tocopherol) are extracted in hexane with anhydrous MgSO4 added to remove water. Complete resolution of the homologs is achieved on a normal phase column and a mobile phase of 0.9% isopropanol in hexane with fluorescence detection. Based on five repetitive assays the mean recoveries were 99.0±1.4, 97.4±2.2%, and 99.5±2.6% for ±-, -, and -tocopherol, respectively. The method is rapid, specific, and accurate for the measurement of vitamin E in margarine and vegetable oil spreads. Further, the method avoids: (1) saponification techniques (2) emulsion forming organic solvent extractions and (3) the use of chlorinated solvents. The limit of detection for ±-, -, and - tocopherol were 23.2, 2.96, and 1.98 g/100g, respectively. The limit of quantitation for ±-, , and - tocopherol were 39.8, 5.00, and 3.02 g/100g, respectively. The vitamin E content of the margarine and spreads ranged from 5.58 to 24.2 ±-TE/100g.

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