Riesling Wines Research Articles

Isolation and Identification of the Hydroxycinnamic Acid Derivatives in White Riesling Wine

High performance liquid chromatography was used for the isolation of the hydroxycinnamic acid derivatives found in White Riesling wine. Identities were confirmed using ultraviolet and mass spectroscopy, and gas, paper, and high performance liquid chromatography. The compounds identified included cis- and trans-caffeoyl tartrate, cis- and trans-p-coumaroyl tartrate and trans-feruloyl tartrate. Evidence is presented to indicate that the cisisomers of caffeoyland p-coumaroyl-tartrate were incorrectly identified as glucose-tartrate-hydroxycinnamic acid esters in a previous report.

Gas-Liquid Chromatographic Determination of Methyl Anthranilate in Wine

Abstract A method is described for the gas-liquid chromatographic determination of methyl anthranilate in wine. Methyl anthranilate is extracted with Freon 113 (1,1,2-trichloro-1,2,2-trifluoroethane), concentrated, and quantitated by comparing the peak area with that of an internal standard (p-di-n-butoxybenzene). A synthetic wine solution (12% ethanol in water) as well as White Riesling and Concord wines containing various concentrations of added methyl anthranilate were analyzed. Recovery of methyl anthranilate in the range of 0.1–10 mg/L averaged 100.26% with an average relative error of 3.94%. The method is both rapid and reliable.

Interpretations of ultraviolet absorption in white wines

AbstractMethods are described for the general analysis of total ultraviolet (u.v.) absorbing constituents of white wines. An elution profile, which is characteristic of the particular wine, is obtained by continuous monitoring of effluent from a dextran gel column at 280 nm. Surprisingly, about half of the total u.v. absorbance in the Riesling wine examined was found to be due to non‐phenolic wine constituents, which are separately eluted in the gel column analysis. These are nucleotidic materials, to which little attention has previously been given in oenology.Data relating to the protein‐tannin fraction, and to nucleotidic and phenolic constituents, are directly obtained by recording the wine elution profiles at 265, 280 and 320 nm. The interpretation of the elution curves and the significance and general utility of this new analytical method are discussed.