Yasuyuki Ueda

Determination of isoflavones in soy bean by high-performance liquid chromatography with amperometric detection

Technique de dosage des 4 principales isoflavones (a activite biologique non negligeable) du soja delipide

Determination of Phenolic Anti-Oxidants in Edible Oil by High-Performance Liquid Chromatography with Amperometric Detector

Abstract A high-performance liquid chromatography (HPLC) with amperometric detection was investigated for the analysis of 2-and 3-tert-butyl-4-hydroxyanisole (BHA), 3,5-di-tert−butyl-4-hydroxytoluene (BHT), and tert−butyl-hydroquinone (TBHQ) in edible oil. The reversed-phase system developed was combined with an amperometric detector, the working electrode of which was made of glassy carbon, in order to compare the sensitivity and selectivity of ultraviolet and fluorometric detection. For the amperometric detection of HPLC, cyclic voltammetry was used to monitor the electrochemical properties of the phenolic antioxidants. A simple isolation procedure, based on the continuous liquid-liquid partition technique, was examined for the extraction and clean up of the antioxidants from edible oil. The recovery rates of BHA, BHT, and TBHQ added salad oil were between 90.2-107.7% in the range of 1-50 ppm of the antioxidants. By the present method, BHA, BHT, and TBHQ were well separated, identified and quantitated w...

Composition of fatty acids and their characteristics in oil of instant Chinese noodles.

Twenty-two kinds of oil samples extracted from instant Chinese noodles were analyzed on their composition of fatty acid methyl esters by GC. Four main fatty acids in the oil were 18 : 1, 16 : 0, 18 : 2, and 18 : 0, and another trace ones detected were 14 : 0, 16 : 1, 17 : 0, 17 : 1, 18 : 3+20 : 0, 20 : 1, and 20 : 2. Constraction values of these four main fatty acids were used to evaluate and to calculate the difference among the six producing companies by a personal computer with the analytical method of principal component analysis. Samples were divided into three groups. The constraction values of company B was similar to that of the palm oil and another ones of companies A and E were also similar to that of the mixed oil with the ratio of 25 to 75 on the palm oil and lard.