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…

Study of Spanish wine sensory analysis data over a 3-year period

This study presents an investigation based on sensory analysis data of Spanish wines with geographical indications collected over a three-year period. Sensory analysis plays a crucial role in assessing the quality, characteristics, and perception of wines. The trained tasting panel at Dolmar Laboratory, accredited for objective sensory evaluation of wines since 2016, has been tasting over 5000 wines. However, it is since 2021, when a computer application for tastings was developed, that the digitalization of data allows for detailed statistical analysis of the results.

Analysis of the interaction of melatonin with glycolytic proteins in Saccharomyces cerevisiae during alcoholic fermentation 

Melatonin is a bioactive compound with antioxidant properties, that has been found in many fermented beverages, such as beer and wine [1]. Indeed, it has been shown that yeast can synthesize melatonin during alcoholic fermentation, although its role inside the cell, as well as the metabolic pathway involved in its synthesis, is still unclear [1]. Recent studies showed that during fermentation, melatonin interacts with different proteins of the glycolytic pathway in both Saccharomyces and non-Saccharomyces yeast, for instance glyceraldehyde 3-phosphate dehydrogenase, pyruvate kinase or enolase [2].

Biodiversity and biocontrol ability of Trichoderma natural populations in soil vineyards from Castilla y León region (Spain)

Trichoderma is a microorganism present in many agricultural soils and some of its species could be used as natural biological control agents. In this work, the presence of natural populations of Trichoderma was estimated in soil vineyard and its biocontrol capacity against Phaeoacremonium minimum, one of the main agent causals of grapevine trunk diseases instead of using pesticides. Moreover, physicochemical variables in soil such as pH, organic matter and nutrients were evaluated to determine a possible correlation to natural populations of Trichoderma.

Reconstructing ancient microbial fermentation genomes from the wine residues of Herod, Roman king of Judea

The fortress of the Herodium, built towards the end of the first century BCE/ante Cristo, on the orders of Herod the Great, Roman client king of Judea, attests the expansion of Roman influence in the eastern Mediterranean. During archaeological excavations of the Herodium in 2017[1], a winery was discovered on the ground floor of the palace, with an assortment of clay vessels in situ, including large dolia – clay fermentation vessels each capable of fermenting up to 300-400 L of wine. Thanks to the recent progresses in the field of paleogenomics[2], we could analyse the organic material consistent with grape pomace at the bottom of these vessels, by extracting and sequencing the DNA using shotgun metagenomics and targeted capture, aiming for enrichment of DNA from fermentation associated microbes.

Bioprotection of grape must by Metschnikowia sp.: genericity and mechanism

The market trend heads to food products with less chemical inputs, including in oenology. During the winemaking process, sulfites are commonly use to avoid microbiological contamination and stabilization of the wine thanks to its antimicrobial and antioxidant activities. Nevertheless, this use is not without consequences on human health and environment, leading for example to allergic reaction and pollution. A biological alternative to these sulfites has emerges: the bioprotection.