terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Role of anthocyanins and copigmentation in flavonol solubility in red wines 

Role of anthocyanins and copigmentation in flavonol solubility in red wines 

Abstract

Over the last years, due to climate change, several red wines, such as the Sangiovese wines, have been often subjected to loss of clarity due to the formation of deposits of fine needle-shaped crystals. This phenomenon turned out to be due to an excess of quercetin (Q) and its glycosides (Q-Gs) in wines. These compounds are synthesized to a large extent when grapes are excessively exposed to UVB radiations in vineyards[1]. Unfortunately, it is not easy to predict the degree of Q precipitation because its solubility strongly depends on the wine and matrix composition[2].  Surprisingly, some red wines rich in anthocyanins, even if contained high amount of Q, did not show any precipitates. Likely anthocyanins favour the solubility of Q since flavonols are among the most powerful cofactors involved in the copigmentation phenomenon. Thus, in this study, the role of anthocyanins in Q solubility was evaluated by adding known amounts of grape-derived anthocyanins into model solutions containing either Q or Q-Gs. The effects of pH and time on the Q solubility, copigmentation as well as on the hydrolysis of Q-Gs were determined. Our data showed that the solubility of Q passed from 5 mg/L to 25 mg/L when the amount of grape-derived anthocyanins added into the model solutions increased from 0 to 500 mg/L. Experimental samples were investigated over 30 days and significant changes in Q solubility, correlated to the variation in copigmentation and in anthocyanins/quercetin ratio, were observed. These results can assist wine producers to better evaluate the level of flavonol precipitation in red wines and to develop appropriate strategies in order to avoid undesired precipitations in bottle.   

Acknowledgements: The authors would like to thank the Biolaffort Company for funding.

References:

1) Martínez-Lüscher J. et al. (2019). Flavonol profile is a reliable indicator to assess canopy architecture and the exposure of red wine grapes to solar radiation. Frontiers in plant science, 10, 10. DOI 10.3389/fpls.2019.00010.

2) Gambuti A. et al. (2020). New insights into the formation of precipitates of quercetin in Sangiovese wines. Journal of Food Science and Technology, 57, 2602-2611. DOI 10.1007/s13197-020-04296-7

DOI:

Publication date: October 5, 2023

Issue: ICGWS 2023

Type: Article

Authors

Alessandra Luciano1, Luigi Picariello1, Martino Forino1, Angelita Gambuti1*

1 Department of Agricultural Sciences, Section of Vine and Wine Sciences, University of Napoli ″Federico II″, Viale Italia, Avellino 83100, Italy

Contact the author*

Keywords

quercetin, quercetin glycosides, solubility, red wines, anthocyanins, copigmentation crystals, precipitation

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Tackling the 3D root system architecture of grapevines: a new phenotyping pipeline based on photogrammetry

Plant roots fulfil important functions as they are responsible for the acquisition of water and nutrients, for anchorage and stability, for interaction with symbionts and, in some cases, for the storage of carbohydrates. These functions are associated with the Root System Architecture (RSA, i.e. the form and the spatial arrangement of the roots in the soil). The RSA results from several biological processes (elongation, ramification, mortality…) genetically determined but with high structural plasticity.

Drought tolerance assessment and differentiation of grapevine cultivars using physiological metrics: insights from field studies

This study aimed to validate a protocol and compare metrics for evaluating drought tolerance in two Vitis vinifera grapevine cultivars under field conditions. Various metrics were calculated to represent the physiological responses of plants to progressive water deficit. Data were collected from Sauvignon Blanc and Chardonnay plants subjected to three irrigation levels during the 2022-2023 season, along with data from three previous seasons. Hydro-escape areas were used to assess the plant’s ability to reduce water potential with decreasing soil water availability.

Time vs drought: leaf age rather than drought drives osmotic adjustment in V. vinifera cv. Pinot Noir

Global warming and increased frequency and/or severity of drought events are among the most threatening consequences of climate change for agricultural crops. In response to drought, grapevine (as many other plants) exhibits osmotic adjustment through active accumulation of osmolytes which in turn shift the leaf turgor loss point (TLP) to more negative values, allowing to maintain stomata opened at lower water potentials1. We investigated the capacity of Pinot noir leaves to modulate their osmotic potential as a function of: (i) time (seasonal osmoregulation), (ii) growing temperatures, and (iii) drought events, to enhance comprehension of the resilience of grapevines in drought conditions. We performed trails under semi-controlled field conditions, and in two different greenhouse chambers (20/15 °C vs 25/20 °C day/night). For two consecutive vegetative seasons, grafted potted grapevines (Pinot noir/SO4) were subjected to two different water regimes for at least 30 days: well-watered (WW) and water deficit (WD).

Genetic prospecting of rainfed viticulture in the region with the largest cultivated area in Chile

The Maule region hosts up to a third of the total area of vineyards in Chile, in an environment where ancient practices inherited from the colonial past coexist with modernity and dynamism that include technified irrigation and fine vines. In the dry land of Maule there is a viticulture that has subsisted with ancient vines and traditions transmitted over generations, and there is little clarity about the origin and classification of the Maule viticulture, giving rise to the use of different concepts as synonyms to describe the ancient, minority, patrimonial or Criollas vines. In order to characterize and protect the ancient material, we studied the genetic diversity of a territorial collection that covers 80% of the communes of the region, prioritizing plants established more than 40-60 years ago.

INTEGRAPE guidelines and tools: an effort of COST Action CA17111

INTEGRAPE was a European interdisciplinary network for “data integration to maximize the power of omics for grapevine improvement” (CA17111, https://integrape.eu/), funded by the European COST Association from September 2018 to 2022. This Action successfully developed guidelines and tools for data management and promoted the best practices in grapevine omics studies with a holistic future vision of: “Imagine having all data on grapevine accessible in a single place”.