A method to quantify all tocopherols and tocotrienols isoforms in chicken meat.

HEWAVITHARANA A. K, LANARI M.C. Y BECU C.

Campinas Brasil

Congreso; International congress of meat science and technology; 2003

Hewavitharana A. K, Lanari M.C. y Becu C. A method to quantify all tocopherols and tocotrienols isoforms in chicken meat. En: Proc. 49th. Int. Congress Meat Sci. & Technol. Campinas Brazil August 2003.  Com Organizador ICOMST (Eds.). Art. Completo.  Campinas Brazil 2003.   We developed a method to study the effect of diet on tocopherol and tocotrienol composition in chicken meat.  Historically a-tocopherol was reported to have the highest biological activity thus most methods available for vitamin E assay were developed exclusively for the determination of a-tocopherol.  Recently, several methods have been developed to determine both tocopherols and tocotrienols in various matrices but no methods were reported for the separation and/or quantitation of all eight vitamin E analogs in animal muscle tissue.  This communication describes the development of such a method. We selected an extraction method that claimed to exhibit the minimum loss of vitamin E and did not include saponification, then further modified to minimise oxidative losses.  Precautions were taken in order to prevent inaccuracies in quantification due to irreversible adsorption of analytes on to the silica column and fluorescence quenching of tocopherol signal at the detection step of chromatographic analysis The accuracy, precision and  robustness of the method were improved by incorporating an internal standard from the extraction step through to the chromatographic analysis. As well, the use of fluorescence rather than UV as the detection mode provided the sensitivity and the selectivity required for the accurate determination of low levels of these homologs in muscle tissue.