No. I (2010): Journal Of Agricultural Sciences - Supplement
Articles

Modern methods to determine vitamin E in foods and feeds

Published October 5, 2010
Camelia Bara
University of Oradea – Faculty of Environmental Protection, 26 General Magheru str., Oradea 2University of Oradea – Faculty of Medicine and Pharmacy
Lucian Bara
University of Oradea – Faculty of Environmental Protection, 26 General Magheru str., Oradea 2University of Oradea – Faculty of Medicine and Pharmacy
Vasile Bara
University of Oradea – Faculty of Environmental Protection, 26 General Magheru str., Oradea 2University of Oradea – Faculty of Medicine and Pharmacy
Ligia Bara
University of Oradea – Faculty of Environmental Protection, 26 General Magheru str., Oradea 2University of Oradea – Faculty of Medicine and Pharmacy
Cristian Domuta
University of Oradea – Faculty of Environmental Protection, 26 General Magheru str., Oradea 2University of Oradea – Faculty of Medicine and Pharmacy
pdf

APA

Bara, C., Bara, L., Bara, V., Bara, L., & Domuta, C. (2010). Modern methods to determine vitamin E in foods and feeds. Acta Agraria Debreceniensis, (I), 53–58. https://doi.org/10.34101/ACTAAGRAR/I/8374

Highly specific and sensitive, the proposed fluorometric method for determining α-tocopherol is robust and fairly fast. It
has been tested in parallel with a conventional thin layer chromatographic method on foods and feeds. The only necessary
cleanup is the usual saponification. The unsaponificable fraction can be extracted with ethyl ether or, preferably, with
Extrelut columns. Reagents and their solvents are added to the isooctane solution before each successive reaction and are
then eliminated by partition with water. The α-tocopherol (α-T) derivative always remains in isooctane. The first step is
nitrosation and elimination of tocopherols and tocotrienols other than α-isomers. α-T is then oxidized to α-tocored (α-TR)
with a mixture of sulfuric acid, ferric chloride, and iodine bromide. Α-TR is then condensed to a new reagent: 4,5-dimethylo-
phenylenediamine. The phenazine formed is strongly fluorescent. Iodine and bromine add to the double bonds of α-
tocotrienol present and quench the fluorescence of its phenazine.

Downloads

Download data is not yet available.