Rapid High‐Performance Liquid Chromatography Determination of Tocopherols and Tocotrienols in Cereals

Abstract

A rapid normal‐phase high‐performance liquid chromatography (NP‐HPLC) method has been developed for rapid determination of the total content of tocopherols (T) and tocotrienols (T3) in cereals. The new method uses a one‐step extraction followed by NP‐HPLC coupled with a fluorescence detector. The new method provides a baseline separation of the critical peaks of beta‐tocotrienol (β‐T3) and gamma‐tocopherol (γ‐T) within a short time of analysis. The extraction step requires no saponification step or addition of antioxidant. Addition of butylated hydroxytoluene (BHT) had no effect on the stability of vitamin E during sampling. The recovery was 96–100%. The method is demonstrated by successful quantification of vitamin E in barley, wheat, and spelt grains, as well as wheat germ and flours from wheat, spelt, and rye.

Oxidative stability of whole wheat bread during storage

“…The content of tocopherol was analysed in accordance to the method described by Nielsen and Hansen (2008). Sample extracts were prepared by dissolving 1 g of bread sample in 30 ml of hexane and placing it in an ultrasound bath for 10 min.…”

Chemical composition of marama bean (Tylosema esculentum)—A wild African bean with unexploited potential

“…The content of tocopherols and tocotrienols was determined in duplicate according to a modification of the method described by Nielsen and Hansen (2008). Using this procedure 1 g of milled sample was extracted with 30 mL hexane by placing the extract in a centrifuge (Sorvall RT 6000D, Buch & Holm A/S) at 6000 rpm for 10 min at 20 8C (in the original method the extraction was done in an ultrasonic bath).…”

Stability of Vitamin E in Wheat Flour and Whole Wheat Flour During Storage

“…The temperature of the column oven was 25°C. The mobile phase contained a solution of hexane, ethyl acetate, and acetic acid (94.6:3.6:1.8) and the flow rate of the mobile phase was set at 1.0 mL/min (Nielsen and Hansen 2008). The tocopherols and tocotrienols were identified by retention time and quantified by use of linear regression from a calibration curve for all eight isomers (1-25 μg/mL).…”