Macrowine 2021
IVES 9 IVES Conference Series 9 The impact of acetaldehyde on phenolic evolution of a free-SO2 red wine

The impact of acetaldehyde on phenolic evolution of a free-SO2 red wine

Abstract

AIMS: Some wine producers, in good years, can produce free-SO2 red wines and decide to add the minimum amount of sulphur dioxide only at bottling. To manage this addition, it is important to know the oxidative history of the wine. Acetaldehyde, the main wine oxidation product, is a powerful electrophile that reacts with numerous wine compounds giving desired products as the stable red polymeric pigments and the less astringent tannins but, also negative off-flavours. Although all these reactions are well known, the border between those increasing wine longevity and those decrementing wine quality is difficult to determine. This study has the aim to investigate the kinetics of consumption of acetaldehyde in red wines to give information useful for the further management of sulphur dioxide.

METHODS: Free-SO2 red wines were spiked with increasing levels of acetaldehyde (from 0 to 190 mg/L) and analysed over time. Chromatic properties and main phenolic classes were analysed by conventional spectrophotometric methods. Small phenolics, polymeric pigments (PP) and polymeric tannins (PT) were detected by HPLC, MS and NMR analysis.  Reactivity of tannins towards BSA and saliva was also determined (1-2-3).

RESULTS: Already two hours after the addition of acetaldehyde the 50% was consumed in reactions with phenolic compounds and the consumption increased over time. Also when a great excess of aldehyde was added (190 mg/L) and after one year of aging a loss of 75% of the initial value was detected. The first compounds that were consumed in reactions with acetaldehyde were anthocyanins and flavanols and a contemporary increase of polymeric pigments and tannins occurred. BSA and saliva reactive tannins increased over time when high concentration of acetaldehyde were added.

CONCLUSIONS

For a correct management of sulphur dioxide when bottling a free-SO2 red wine the content of acetaldehyde and phenolic strong reactants (anthocyanins and flavanols) should be determined to limit or favour further acetaldehyde reactions

DOI:

Publication date: September 14, 2021

Issue: Macrowine 2021

Type: Article

Authors

Francesca Coppola

Department of Agricultural Sciences, Division of Vine and Wine Sciences, University of Naples Federico II, Avellino, (Italy),Luigi Picariello, Martino Forino,  Luigi Moio, Angelita Gambuti Department of Agricultural Sciences, Division of Vine and Wine Sciences, University of Naples Federico II, Avellino, (Italy)

Contact the author

Keywords

wine longevity, polyphenols

Citation

Related articles…

Effects of urea and nano-urea foliar treatments on the aromatic profile of Monastrell wines

Foliar application of urea has proven to be an effective method for increasing the amino acid content in grapes, especially when the vineyard has additional nitrogen needs. These treatments can prevent problems of stucking fermentation during winemaking.

Soil management of interrow spacing as an important factor to protect the vineyard soils from runoff and erosion under the Mediterranean climate

Nearly one third of the Herault vineyard (south of France) is planted on soils very sensitive to water runoff and erosion

Tutela legale delle denominazioni di origine nel mondo (con aspetti applicativi)

Uno degli aspetti più importanti nel commercio internazionale dei vini a denominazione è quello del riconoscimento dei diritti di esclusiva garantiti sui e dal territorio geografico d’o­rigine. Al fine di cautelarsi nei confronti della sempre più agguerrita concorrenza mondiale, è opportuno adottare adeguate protezioni ufficiali e legali delle denominazioni che possono derivare sia dalla “naturalità” del prodotto stesso che dalla “originalità” più particolare.

Assessment of O2 consumption, a new tool to select bioprotection yeast strains

Reduction of sulfur dioxide during winemaking is a request from the wine industry. To replace sulfur dioxide, various alternatives exist, including bioprotection by yeast inoculation. This practice consists in adding non-Saccharomyces yeasts directly on the grapes or must.

Phenolic composition and chromatic characteristics of blends of cv. Tempranillo wines from vines grown with different viticultural techniques in a semi-arid area

The quality and color stability of red wines are directly related to content and distribution of phenolic compounds. However, the climate change produces the asynchrony between the dates of technological and maturity of grapes. The crop-forcing technique (CF) restores the coupling between phenolic and technological ripeness while limits vineyard yields. Blending of wines is frequently used to equilibriate composition of wines and to increase their stability, color and quality. The aim of the present work is to study the phenolic composition and color of wine blends made with FW (wines from vines subjected to CF) and CW (wines for vines under the usual cultivation practices).