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…

The colour pattern of flower arrangements influence wine tasters’ sensory description

The arrangements of flowers and wine counterparts are inextricably linked. Whether a fundamental aspect of tablescaping or acolytes to broader entertainment rituals, they have an entangled history since ancient times. The aim of this contribution is to verify the influence of visually delicate and robust flower arrangements on individual description of wines. Changes in the sensory description of wines were investigated during subjects’ (thirty-two participants) exposure to three different conditions: the presence of delicate, robust, or totally absent flower arrangements. In each condition, the same two wines were blind tasted: a wine previously defined as delicate – a Pinot Noir from Australia, and a wine known for its robust character – a Tannat from Uruguay.

The characterization of Vitis vinifera L cv. Cabernet sauvignon: the contribution of Ecklonia maxima seaweed extract

Biostimulants and biofertilizers are considered environmentally friendly and cost-effective alternatives to synthetic fertilizers, plant growth regulators and crop improvement products. Broadly, plant biostimulants are expected to improve nutrient use efficiency, tolerance to abiotic stress, quality traits and availability of nutrients in the soil or rhizosphere. Currently, seaweed extracts account for more than 33% of the total plant biostimulant market. Within this category, Ascophyllum nodosum (AN), is the most widely studied and applied in biostimulant formulations.

Crown procyanidin quantification in red wines, rosé wines and Port wines

Condensed grape tannins play a major role in the organoleptic properties and quality of red wine. Recently, a new sub-family of macrocyclic condensed tannins has been identified in red wine and named “crown tannins”. Indeed, the first compound of the family identified and characterised by NMR was the crown procyanidin tetramer which is composed of a macrocyclic structure composed of four (-)-epicatechins link together by B-type interflavanoid linkage in the following an alternative sequences of C4-C8 and C4-C6 linkage. The 3D structure of this unusual crown procyanidin family reveals a central cavity in the molecule [1].

Effect of foliar application of Ca, Si and their combination on grape volatile composition

Calcium (Ca) is an important nutrient for plants which plays key signaling and structural roles. It has been observed that exogenous Ca application favors the pectin accumulation and inhibition of polygalacturonase enzymes, minimizing fruit spoilage. Silicon (Si) is a non-essential element which has been found to be beneficial for improving crop yield and quality, as well as plant tolerance to diverse abiotic and biotic stress factors. The effect of Si supply to grapevine has been assessed in few investigations, which reported positive changes in grape quality and must composition.

Toasting and grain effect on Tempranillo red wine aged in Quercus petraea barrels

The barrel-making process is widely recognized as a crucial practice that affects the composition of barrel-aged wine. After the drying process, the staves are considered ready for barrel assembly, which includes the processes of bending and toasting the barrel structure. Toasting is considered one of the most critical stages in determining the physical and chemical composition of the staves, which can influence the chemical and sensory composition of the wine aged in barrels made from them [1].