title: Determination of organic acids by high-performance liquid chromatography with electrochemical detection during wine brewing.
abstract: Voltammetric determination of acids by means of the electrochemical reduction of quinone was applied to high-performance liquid chromatography (HPLC) with electrochemical detection (ED) for determining organic acids in fruit wines. A two-channel HPLC-ED system was fabricated by use of an ion-exclusion column and an electrochemical detector with a glassy carbon working electrode. Aqueous solution of 0.1 mM HClO(4) and ethanol containing 2-methyl-1,4-naphthoquinone served as a mobile phase and reagent solution, respectively. Determination of acetic, citric, lactic, malic, succinic, and tartaric acids was made by measuring the peak areas of the flow signals due to the reduction current of quinone caused by the eluted acids. The peak area was found to be linearly related to the acid amount ranging from 0.1 to 40 nmol per 20 microL injection. The present method was characterized by reproducibility with the simple and rapid procedure without derivatization of analytes. The method was shown as an effective means for following acid contents in fruit juices during fermentation with wine yeast.
authors.affiliation: Department of Analytical Chemistry, School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kotani
authors.forename: Yuji
authors.initials: Y
authors.lastname: Miyaguchi
authors.forename: Eiji
authors.initials: E
authors.lastname: Tomita
authors.forename: Kiyoko
authors.initials: K
authors.lastname: Takamura
authors.forename: Fumiyo
authors.initials: F
authors.lastname: Kusu
mesh_terms: D002264:Carboxylic Acids / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005285:Fermentation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014920:Wine / Q000032:analysis*
chemical_list: D002264:Carboxylic Acids