IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Anthocyanins Chemistry During Red Wine Ageing

Anthocyanins Chemistry During Red Wine Ageing

Abstract

Anthocyanins are the main pigments present in young red wines, being responsible for their intense red color. These pigment in aqueous solutions occur in different forms in equilibrium that are dependent on the pH. At low pH values, anthocyanins are present in their red flavylium cation form but when the pH increases for values between 3 and 6, the flavylium cation form is hydrated yielding to the colorless hemiketal form that is in equilibrium with the pale yellow cis-chalcone form through tautomerization. Simultaneously, the flavylium cation is deprotonated to the respective violet neutral quinoidal base that at higher pH values can be deprotonated yielding the blue anionic quinoidal base. At wine pH (3-4), anthocyanin would be expected to be present mainly in their non-colored hemiketal form. However, the flavylium cation is the main form present in red wines. This is the result of its stabilization by different co-pigmentation mechanisms such as self-association and interaction with other wine components. Oligomeric anthocyanins (dimeric and trimeric) were also found to occur in red grapes and respective wines. Moreover, it was showed that trimeric anthocyanins reactivity is strongly dominated by acid-base chemistry, with the reaction sequence hydration – tautomerization – isomerization accounting less than 10% of the overall reactivity, which seems to indicate that polymerization may be a natural stabilization mechanism for the red color of anthocyanins. In addition, throughout wine ageing and maturation, the concentration of anthocyanins decreases dramatically and a color change is observed from red/violet to a more brick hue due to the formation of several anthocyanin-derivatives such as A and B-type vitisins and other pyranoanthocyanins that have been described in the literature over the years. Those compounds formed present a more stable color than their precursors (anthocyanins).  During this process, anthocyanins can yield polymeric pigments by their reaction with flavanols (directly or mediated by aldehydes). Moreover, it has been demonstrated that A-type vitisins (the main pyranoanthocyanins found in red wines) can also react with other wine components giving origin to polymeric pigments with different colors ranging from yellow to turquoise blue. Polymeric pigments are described to play an important role in the long-term color stability of aged red wines, however there is still a lot to know about their identity, chemical pathways and real contribution to the color displayed by red wines.

 Apart from the chromatic features that anthocyanins and anthocyanin-derived pigments are able to confer to red wines, it has also been demonstrated that this pigments can be involved in astringency and bitterness perception of red wines.

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Joana Oliveira1

1LAQV – REQUIMTE – Department of Chemistry and Biochemistry of Faculty of Science of University of Porto, Rua do Campo Alegre S/N, 4169-007 Porto, Portugal

Contact the author

Keywords

Anthocyanins; chemistry; red wine ageing; anthocyanin-derived pigments; organoleptic properties

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Adaptation to soil and climate through the choice of plant material

Choosing the rootstock, the scion variety and the training system best suited to the local soil and climate are the key elements for an economically sustainable production of wine. The choice of the rootstock/scion variety best adapted to the characteristics of the soil is essential but, by changing climatic conditions, ongoing climate change disrupts the fine-tuned local equilibrium. Higher temperatures induce shifts in developmental stages, with on the one hand increasing fears of spring frost damages and, on the other hand, ripening during the warmest periods in summer. Expected higher water demand and longer and more frequent drought events are also major concerns. The genetic control of the phenotypes, by genomic information but also by the epigenetic control of gene expression, offers a lot of opportunities for adapting the plant material to the future. For complex traits, genomic selection is also a promising method for predicting phenotypes. However, ecophysiological modelling is necessary to better anticipate the phenotypes in unexplored climatic conditions Genetic approaches applied on parameters of ecophysiological models rather than raw observed data are more than ever the basis for finding, or building, the ideal varieties of the future.

Local adaptation tools to ensure the viticultural sustainability in a changing climate

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Effect of vigour and number of clusters on eonological parameters and metabolic profile of Cabernet Sauvignon red wines

Vegetative growth and yield are reported to affect grape and wine quality. They can be controlled through different techniques linked to vine management. The objective of this research was to determine the effect of vine vigour and number of clusters per vine on physicochemical composition and phenolic profile of red wines. The experiment was carried out during two vegetative cycles, with cv. Cabernet Sauvignon grafted onto Paulsen 1103. Three vine vigour were defined, according to shoot weight at previous harvests, being low, medium and high. Five treatments of number of clusters were used for each vigour, with 15, 22, 29, 36, and 45 clusters per vine. Grapes from all treatments were harvested in the same day from Brix and total acidity criteria. Thirty days after bottling, classical analyzes and phenolic compounds were performed. As results, different responses were obtained from each vintage. In 2020, a dry season from veraison to harvest, grapes and wines obtained from low vigour treatment and 45 clusters per vine was the highest in sugar and alcohol content respectively, while grapes and wines from high vigour and 15 clusters presented the lowest sugar and alcohol content. Total anthocyanins were higher in treatment with low vigour and 15 clusters, while the lowest amounts were found in low vigour with 45 clusters, as well as medium and high vigour with 36 clusters per vine. Total tannins were higher in high vigour with 22 clusters and medium vigour with 29 clusters, while were lower in low vigour with 36 clusters. In 2021, a wet season at harvest, responses were different, and great variations were observed between treatments. As conclusions, yield and vine vigour had strong influence on grape and wine quality, promoting different enological potentials on which can be indicated/used for aging strategies of red and even rosé wines.

Legacy of land-cover changes on soil erosion and microbiology in Burgundian vineyards

Soils in vineyards are recognized as complex agrosystems whose characteristics reflect complex interactions between natural factors (lithology, climate, slope, biodiversity) and human activities. To date, most of the unknown lies in an incomplete understanding of soil ecosystems, and specifically in the microbial biodiversity even though soil microbiota is involved in many key functions, such as nutrient cycling and carbon sequestration. Soil biological properties are indicative of soil quality. Therefore, understanding how soil communities are related to soil ecosystem functioning is becoming an essential issue for soil strategy conservation. Here, we propose to assess the importance of land-cover history on the present-day microbiological and physico-chemical properties. The studied area was selected in the Burgundian vineyards (Pernand-Vergelesses, Burgundy, France) where land occupation has been reconstructed over the last 40 years. Soil samples were collected in five areas reflecting various land cover history (forest, vineyards, shifting from forest to vineyards). For each area, physico-chemical parameters (pH, C, N, P, grain size) were measured and DNA was extracted to characterize the abundance and diversity of microbial communities. The obtained results show significant differences in the five areas suggesting that present-day microbial molecular biomass and bacterial taxonomic is partly inherited from past land occupation. Over longer period of time, such study of land-uses legacies may help to better assess ecosystem recovery and the impact of management practices for a better soil quality and vineyards sustainability.

Mapping and tracking canopy size with VitiCanopy

Understanding vineyard variability to target management strategies, apply inputs efficiently and deliver consistent grape quality to the winery is essential. However, despite inherent vineyard variability, the majority are managed as if they are uniform. VitiCanopy is a simple, grower-friendly tool for precision/digital viticulture that allows users to collect and interpret objective spatial information about vineyard performance. After four years of field and market research, an upgraded VitiCanopy has been created to achieve a more streamlined, technology-assisted vine monitoring tool that provides users with a set of superior new features, which could significantly improve the way users monitor their grapevines. These new features include:
• New user interface
• User authentication
• Batch analysis of multiple images
• Ease the learning curve through enhanced help features
• Reporting via the creation of colour maps that will allow users to assess the spatial differences in canopies within a vineyard.
Use-case examples are presented to demonstrate the quantification and mapping of vineyard variability through objective canopy measurements, ground-truthing of remotely sensed measurements, monitoring of crop conditions, implementation of disease and water management decisions as well as creating a history of each site to forecast quality. This intelligent tool allows users to manage grapevines and make informed management choices to achieve the desired production targets and remain profitable.