terclim by ICS banner
IVES 9 IVES Conference Series 9 VOLTAMETRIC PROFILING OF RED WINE COMPOSITION DURING MACERATION: A STUDY ON FOUR GRAPE VARIETIES

VOLTAMETRIC PROFILING OF RED WINE COMPOSITION DURING MACERATION: A STUDY ON FOUR GRAPE VARIETIES

Abstract

During red wine vinification, maceration allows the must, and consequently the wine, to be enriched with several compounds that contribute to the creation of the typical organoleptic characteristics of red wines. Among these, extraction of polyphenols (PPs) during maceration is a major process of enological interest.

The purpose of this study was the evaluate the suitability of a rapid analytical approach based in linear sweep voltammetry to monitor PPs extraction during vinification. Four red grape varieties were investigated, and fermentations were carried out with three different yeasts in triplicate. The density was evaluated daily and every 48h samples were taken to monitor changes in voltametric profiles and in the anthocyanins, polyphenols and precipitable tannins content.

The voltametric profiles of the wines were monitored using disposable screen-printed carbon electrodes with the working and counter electrode in carbon paste and an Ag/AgCl reference electrode. A drop of sample was loaded onto the sensor, and linear sweep voltammograms were acquired between 0-1200mV at a scan rate of 100mV/s. Analyzing the voltammograms, it was possible to observe differences between varieties and, within each variety, the temporal evolution of maceration.

In the second-derivative voltammograms, a positive peak was observed at low potentials, it increases initially showing a maximum after 7 days of fermentation. This peak is associated with the more easily oxidized compounds in wine. Another region of the voltammogram that shows a trend associated with the progress of fermentation is that around 440mV; in this region the negative peak reaches a maximum after 24 h after the start of maceration and then slowly decreases. This region has been associated with the concentration of monomeric anthocyanins and flavanols. The negative peak around 780mV results initially influenced by the presence of free SO₂, when SO₂ is bound the peak decreases in intensity and then increases again during maceration. By constructing PLS-R models for the concentration of anthocyanins, polyphenols and precipitable tannins the best pre-processing method resulted the second derivative and good regression models were obtained (R2 from 0.75 to 0.95).

In conclusion, this study provides a first proof of concept of the suitability of a simple analytical approach based on linear sweep voltammetry to monitor the evolution of phenolic composition during red wine maceration.

 

1. P. A. Kilmartin, Electrochemistry applied to the analysis of wine: A mini-review, Electrochemistry Communications, 2016, 67, 39-42
2. M. Ugliano, Rapid fingerprinting of white wine oxidizable fraction and classification of white wines using disposable screen printed sensors and derivative voltammetry, Food Chemistry, 2016, 212, 837-843
3. C. Ferreira, M.P. Sáenz-Navajas, V. Carrascón, T. Næs, P. Fernández-Zurbano, V. Ferreira, An assessment of voltammetry on disposable screen printed electrodes to predict wine chemical composition and oxygen consumption rates, Food Chemistry, 2021, 365, 130405

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Leonardo Vanzo¹, Nicola Dalla Valle¹, Giacomo Cristanelli¹, Davide Slaghenaufi¹, Maurizio Ugliano¹

1. Department of Biotechnology, University of Verona

Contact the author*

Keywords

Maceration, Voltammetry, Polyphenols, Red wine

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

EFFECTS OF LEAF REMOVAL AT DIFFERENT BUNCHES PHENOLOGICAL STAGES ON FREE AND GLYCOCONJUGATE AROMAS OF SKINS AND PULPS OF TWO ITALIAN RED GRAPES

Canopy-management practices are applied in viticulture to improve berries composition and quality, having a great impact on primary and secondary grape metabolism. Among these techniques, cluster zone leaf removal (defoliation) is widely used to manage air circulation, temperature and light radiation of grape bunches and close environment. Since volatiles are quantitatively and qualitatively influenced by the degree of fruit ripeness, the level of solar exposure, and the thermal environment in which grapes ripen, leaf removal has been shown to affect volatile composition of grape berries [1].

Read More

AROMA AND SENSORY CHARACTERIZATION OF XINOMAVRO RED WINES FROM DIFFERENT GREEK PROTECTED DESIGNATIONS OF ORIGIN, EFFECT OF TERROIR CHARACTERISTICS

The quality of wines has often been associated with their geographical area of production. The aim of this work was to characterize Protected Designation of Origin (PDO) Xinomavro red wines from different geographical areas of Amyndeon and Naoussa in Northern Greece, elaborated with variables that contribute to their differentiation, such as soil characteristics, altitude, monthly average temperature and rainfall.
Xinomavro fruit parcels from different vineyards within the two PDO zones (5 PDO Naoussa and 6 PDO Amyndeon) were vinified following a standard winemaking process. A total of 25 aroma compounds were quantified using gas chromatography-mass spectrometry (GC-MS) with simultaneous full scan and selected ion monitoring for data recording, and odor activity values (OAVs) were determined.

Read More

WINE WITHOUT ADDED SO₂: OXYGEN IMPACT AND EVOLUTION ON THE POLYPHENOLIC COMPOSITION DURING RED WINE AGING

SO₂ play a major role in the stability and wine during storage. Nowadays, the reduction of chemical input during red winemaking and especially the removing SO₂ is a growing expectation from the consumers. Winemaking without SO₂ is a big challenge for the winemakers since the lack of SO₂ affects directly the wine chemical evolution such as the phenolic compounds as well as its microbiological stability.

Read More

CHARACTERIZATION OF ENOLOGICAL OAK TANNIN EXTRACTS BY MULTI-ANALYTICAL METHODS APPROACH

Oak tannin extracts are commonly used to improve wine properties. The main polyphenols found in oak wood extracts are ellagitannins¹ that release ellagic acid upon hydrolysis and comprise numerous structures². Moreover, oak tannin extracts contain other compounds giving a complex mixture. Consequently, the official OIV method based on gravimetric analysis of the tannin fraction adsorbed on polyvinylpolypyrrolidone is not sufficient to describe their composition and highlight their chemical diversity.

Read More

TARTARIC STABILIZATION MAY AFFECT THE COLOR AND POLYPHENOLIC COMPOSITION OF TANNAT RED WINES FROM URUGUAY

Tartrate precipitation affects the properties of wines, due to the formation of crystals that cause turbidity, even after being bottled. The forced tartaric stabilization is carried out frequently for young wines, through various physicochemical procedures. The traditional treatment for tartaric stabilization is refrigeration, but it can have a negative effect on wine’s sensory properties, and particularly on the color of red wines. The aim of this study was to evaluate the effect of different tartaric stabilization options on the color and phenolic composition of Tannat red wines from Uruguay.

Read More