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…

A blueprint for managing vine physiological balance at different spatial and temporal scales in Champagne

In Champagne, the vine adaptation to different climatic and technical changes during these last 20 years can be seen through physiological balance disruptions. These disruptions emphasize the general grapevine decline. Since the 2000s, among other nitrogen stress indicators, the must nitrogen has been decreasing. The combination of restricted mineral fertilizers and herbicide use, the growing variability of spring rainfall, the increasing thermal stress as well as the soil type heterogeneity are only a few underlying factors that trigger loss of physiological balance in the vineyards. It is important to weigh and quantify the impact of these factors on the vine. In order to do so, the Comité Champagne uses two key-tools: networking and modelization. The use of quantitative and harmonized ecophysiological indicators is necessary, especially in large spatial scales such as the Champagne appellation. A working group with different professional structures of Champagne has been launched by the Comité Champagne in order to create a common ecophysiology protocol and thus monitor the vine physiology, yearly, around 100 plots, with various cultural practices and types of soil. The use of crop modelling to follow the vine physiological balance within different pedoclimatic conditions enables to understand the present balance but also predict the possible disruptions to come in future climatic scenarios. The physiological references created each year through the working group, benefit the calibration of the STICS model used in Champagne. In return, the model delivers ecophysiology indicators, on a daily scale and can be used on very different types of soils. This study will present the bottom-up method used to give accurate information on the impacts of soil, climate and cultural practices on vine physiology.

Influence of nitrogen source on expression of genes involved in aroma production in Saccharomyces uvarum

Saccharomyces uvarum has interesting properties that can be exploited for the production of fermented beverages. Particularly, the cryotolerance and capacity to produce high amounts of volatile compounds offers new opportunities for the wine industry.

Viticultural landscape: history of a challenging coexistence between grapevines and humans 

Vitis vinifera is the most grown grapevine species, which originated about 6 million years ago in the trans-caucasian area as the ancestral (wild) type v. Vinifera spp. Sylvestris. On the other hand, the human being (homo sapiens) is much younger since he originated about 300.000 years ago in north africa.

Grapevine adaptation to drought and resistance to Neofusicoccum parvum, causal agent of Botryosphaeria dieback

The sustainability of viticulture in response to climate change has been addressed mainly considering agronomic impacts, such as water management and diseases, either separately or together.
In grapevines, there is strong evidence that different genotypes respond differently to biotic and abiotic stresses. A screening was conducted on various local cultivars in response to drought and Neofusicoum parvum infection aiming to evaluate their susceptibility to abiotic stress and resistance to fungal diseases.

Grafting, the most sustainable way to control phylloxera over 150 years

Just over 150 years ago, phylloxera, daktulosphaera vitifoliae, was introduced to europe, and particularly france, from north america via imports of american vitis plants. This aphid, with its complex biology and life cycle, has spread rapidly to most vineyards, causing rapid and lethal decline of v. Vinifera vines due to the primary and secondary damage it causes to the roots. In response to this pest, and given the economic importance of the french wine sector, professional representatives organised into ‘agricultural societies’, scientists and public authorities rallied together to identify the exact causes, seek solutions and try to stem the serious socio-economic crisis that ensued.