Macrowine 2021
IVES 9 IVES Conference Series 9 How the management of ph during winemaking affects acetaldehyde evolution and the formation of polymeric phenolics over the red wine aging

How the management of ph during winemaking affects acetaldehyde evolution and the formation of polymeric phenolics over the red wine aging

Abstract

AIM: The aim of this study is to evaluate the role of pH on both the acetaldehyde chemistry and wine phenolics evolution over the aging period. In addition, the effect of both an early (on musts) and late (on wines soon after the end of the fermentation) acidification was evaluated.

METHODS: The experimental design consisted in the preparation of 7 wines from the same batch of grapes fermented in a first tank at the original pH of 3.2 (3.2W) and two other tanks in which the pH was adjusted to 3.5 (3.5W) and 3.9 (3.9W). On the third day of fermentation, and one week after the end of the fermentation-maceration process some aliquots of both 3.5W and 3.9W were treated to reach a 3.2 pH to afford four more wines. Polymeric pigments and phenolics were evaluated by spectrophotometry, MS and NMR techniques, acetaldehyde and anthocyanins by HPLC-DAD and reactivity of tannins towards saliva by electrophoresis. Wines were analyzed soon after the end of the fermentation and after one-year aging.

RESULTS: By increasing the pH level from 3.2 to 3.9, the amount of low polymerized flavans, individual anthocyanins and tannins reactive to BSA and saliva decreased. Conversely, an increase of acetaldehyde, of pigments resistant to the bleaching, and of ethylene-linked polymeric pigments was detected. After one year of aging, wines treated to reach a 3.2 pH significantly differ from 3.2W in acetaldehyde, tannins reactive towards proteins and polymeric pigments. This behavior was more evident when the acidification was carried out soon after the end of the fermentation-maceration process.

CONCLUSIONS

High pH values favor the polymerization of phenolics over the wine aging and results suggested that the effect is predominant when pH was increased during the fermentation, hence successive pH modulations have little (if any) effect on some typical reactions occurring during wine aging.

DOI:

Publication date: September 14, 2021

Issue: Macrowine 2021

Type: Article

Authors

Angelita Gambuti

Department of Agricultural Sciences, University of Napoli “Federico II”- Enology Sciences Section, Viale Italia, 83100, Avellino, Italy, Luigi PICARIELLO, Department of Agricultural Sciences, University of Napoli “Federico II”- Enology Sciences Section, Viale Italia, 83100, Avellino, Italy. Martino  FORINO, Department of Agricultural Sciences, University of Napoli “Federico II”- Enology Sciences Section, Viale Italia, 83100, Avellino, Italy Alessandra RINALDI, Department of Agricultural Sciences, University of Napoli “Federico II”- Enology Sciences Section, Viale Italia, 83100, Avellino, Italy. Biolaffort, 126 Quai de la Souys, 33100 Bordeaux, France. Luigi MOIO, Department of Agricultural Sciences, University of Napoli “Federico II”- Enology Sciences Section, Viale Italia, 83100, Avellino, Italy.

Contact the author

Keywords

red wine, aging, ph, polyphenols

Citation

Related articles…

Consumer perception of wine bottle weight and its impact on sustainability

In the context of sustainability, this study evaluated consumer perception regarding the impact of glass bottle weight on wine valuation.

Grape ripening and wine style: synchronized evolution of aromatic composition of shiraz wines from hot and temperate climates of Australia

Grape ripening is a process driven by the interactions between grapevine genotypes and environmental factors. Grape composition is largely responsible for the production

Exploring microbial interactions between Saccharomyces cerevisiae and non-Saccharomyces yeast starters in vinification

Winemaking is a complex microbial process involving the co-existence and interactions of various microorganisms [1].

To what extent does vine balance actually drive fruit composition?

Context and purpose of the study ‐ Vine balance is a concept describing the relationship between carbon assimilation (usually estimated using a measure of vine vigour, e.g. pruning weight) and its utilisation for fruit production (usually estimated using harvest yield). Manipulating vine balance through leaf area or crop load adjustments affects the proportion of the vine’s total carbohydrate production required to mature the fruit. It is commonly considered that composition of the berry, and resulting wine, is strongly affected by vine balance.

Sensory impact of acetaldehyde addition in Syrah red wines

Acetaldehyde is a volatile carbonyl compound synthetized by yeast during alcoholic fermentation, but it can also be formed by oxidation of ethanol during wine aging [1]. At low concentration, it enhances the fruity aroma, however, at higher levels, it can generate the appearance of notes of bruised and rotten apple [2]. From a chemical point of view, acetaldehyde is a reactive low-