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…

Vineyard management practices to reduce sugar content on ‘Monastrell’ grapes

Climate change is resulting in more dry and hot summers, accelerating grape ripening and increasing berry sugars concentration. This results in wines with a higher alcohol content, which has a negative impact on wine quality, as well as, on consumer health. Agronomic practices that minimize these effects on berry composition and, consequently, on wine quality must be defined. In this work, different management practices have been assessed on rainfed ‘Monastrell’ grapevines in Jumilla (Murcia, Spain) from 2021 to 2023 vintages. Mulching, shading, application of kaolin and different types of pruning were evaluated, among others field adaptation practices.

Read More

Metabolomic profiling of heat-stressed grape berries 

The projected rise in mean air temperatures together with the frequency, intensity, and length of heat waves in many wine-growing regions worldwide will deeply impact grape berry development and quality. Several studies have been conducted and a large set of molecular data was produced to better understand the impact of high temperatures on grape berry development and metabolism[1]. According to these data, it is highly likely that the metabolomic dynamics could be strongly modulated by heat stress (HS).

Read More

Application of UV-B radiation in pre- and postharvest as an innovative and sustainable cultural practice to improve grape phenolic composition

Ultraviolet radiation (UVR) is a minor part of the solar spectrum, but it represents an important ecological factor that influences many biological processes related to plant growth and development. In recent years, the application of UVR in agriculture and food production is emerging as a clean and environmentally friendly technology.
In grapevine, many studies have been conducted on the effects of ambient levels of UVR, but there are few considering the effects of UV-B application on grape phenolic composition under commercial growing or postharvest conditions.

Read More

A novel approach for the identification of new biomarkers of wine consumption in human urine using untargeted metabolomics

Wine is one of the most representative components of Mediterranean diet. Moderate wine intake together with food, has been positively correlated with reduced risk of many chronic diseases. This beneficial effect seems to be ascribed to elevated polyphenolic content of wine [1]. Traditional approaches for the identification of wine biomarkers consumption include targeted metabolomics that focuses on the quantification of well-defined metabolites, losing a valuable information about a massive number of compounds. On the other hand, untargeted metabolomics can disclose a large quantity of signals corresponding to potential biomarkers in a single analysis with high sensitivity and resolution.

Read More

Addition of glutathione-rich inactivated yeasts to white musts: effects on wine composition and sensory quality

Glutathione plays a key role in preventing some oxidative processes during winemaking. This molecule limits the must enzymatic oxidation, reacts with caffeic acid and generates a colourless compound that prevents subsequent browning. It also has a protective effect on wine aroma, preventing the oxidation of the volatile compounds with a high sensory impact.

Read More