Determination of Free Proline and Monosaccharides in Wine Samples by High-Performance Anion-Exchange Chromatography with Pulsed Amperometric Detection (HPAEC-PAD)

Abstract

A sensitive and selective analytical method for the simultaneous separation and quantitative determination of proline and free monosaccharides in wine samples by high-performance anion-exchange chromatography coupled with pulsed amperometric detection is described. Under optimized experimental conditions, a complete separation was obtained in less than 30 min, using an isocratic elution with 10 mM NaOH and 1 mM Ba(OAc)(2). No postcolumn addition of strong bases to the eluent for enhancing detection sensitivity was needed. Upon 25-fold sample dilution and purification to avoid interference of tannins, pigments, and phenolic compounds, the fingerprinting of common monosaccharides (i.e., arabinose, glucose, fructose, galactose, and xylose) and proline in wines, musts, and vinegars can be easily accomplished. The method allows high recovery and satisfies the necessary requirements for accuracy, repeatability, and sensitivity. Values obtained for proline content ranged from 470 to 1190 mg/L in "Aglianico" red wines (mean value, 870 +/- 192 mg/L, n = 21) and from 168 to 286 mg/L in white wines (mean value, 208 +/- 32 mg/L, n = 11). Lower levels were found in musts of red and white grapes, 550 and 87 mg/L, respectively. The lowest content of proline, ca. 10 mg/L, was found both in white and red vinegars.

Rapid analysis of carbohydrates in aqueous extracts and hydrolysates of biomass using a carbonate-modified anion-exchange column

“…Analytes of interest in biofuel research typically include the monomeric sugars glucose, xylose, arabinose, galactose, mannose, and fructose, as well as sucrose, maltose, and cellobiose dimers. Rapid analysis of these carbohydrates in complex samples has remained a challenge [9,10], not only for the biofuels industry, but also for food and beverage industries [11][12][13][14].…”

Determination of Low Molecular Weight Carbohydrates in Cabernet Sauvignon Red Wines

“…Electrochemical procedures for the enzymatic determination of glucose and fructose were developed [6][7][8] . Sugars in wine can be determined by HPLC, using different detectors [9][10][11][12] . The addition of sucrose in red wine is allowed in many countries of the European Community, such as Germany, Belgium, Denmark, Ireland, Poland, Sweden, United Kingdom, Czech Republic and in some French departments 13 .…”

Determination of proline–hydroxyproline dipeptide in rat urine by high-performance anion-exchange chromatography coupled with pulsed amperometric detection

“…Here we report the development of a method based on HPAEC-PAD for the simultaneous determination of proline (Pro), Hyp, and PHP that does not require hydrolysis or derivatization steps. While previous studies have used HPAEC-PAD to determine Pro or/and Hyp in food samples [8,9], its application to the determination of PHP in rat urine has not been reported. In addition, we optimized the method by examining various analytical conditions such as mobile phases, pushing agents, column temperatures, and potential waveforms, making improvements as needed.…”