67B-35 |
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S. M. LEE, K. H. Mo, E. J. Park, and J. Lee. Department of Food Science and Technology, Chungbuk National University, 48 Gaeshin-dong, Heungduk-gu, Cheong-ju, 361-763, South Korea For the determination of vitamin E using HPLC, the most critical and time consuming step is the quantitative extraction of all vitamin E forms from samples. In order to release the vitamin compounds, various extraction methods, depending on the nature of the sample, have been applied. In many cases, Soxhlet extraction and saponification have been used for the determination of vitamin E cereal grains and their products. Recently, direct solvent extraction was applied to extract vitamin E in nuts and seeds and was proven to yield higher values for each tocopherol homolog compared to other methods. The objective of this study was to compare three extraction methods, direct solvent extraction, saponification, and Soxhlet extraction, for their usefulness as extraction methods to determine vitamin E in cereal grains and their products. Three different extraction methods were compared to determine vitamin E in cereal grains and their products. Saponification used alkaline hydrolysis followed by solvent extraction. Direct solvent extraction included dispersing the sample in hot water, addition of isopropanol and MgSO4, and extraction of the analytes with extracting solvent with Polytron homogenization. Using Soxhlet extraction, the samples were extracted in a Soxhlet apparatus with hexane containing BHT. Vitamin E in 14 cereal grains and 6 cereal products were analyzed by three different extraction methods. Generally, the highest values of a-tocopherol equivalent were observed from direct solvent extraction followed by Soxhlet extraction and saponification. Also, the analytical method validation parameters such as accuracy, precision, limit of detection, limit of quantitation, and specificity were calculated to further ensure the method°¯s validity. In this study, three different extraction methods were compared and the direct solvent extraction proved to be the best method for the determination of tocopherol homologs in the cereal samples. This method was fast and accurate. In particular, this method allows quantitation of a-tocopheryl acetate and naturally occurring tocopherols for accurate assessment of total vitamin E activity in the fortified cereals.
Session 67B, Food Chemistry: Antioxidants and bioactive agents
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