Macrowine 2021
IVES 9 IVES Conference Series 9 Kinetic investigations of the sulfite addition on flavanols

Kinetic investigations of the sulfite addition on flavanols

Abstract

Sulfonated monomeric and dimeric flavan-3-ols are recently discovered in wine and proved to have great importance in understanding wine chemistry and quality [1, 2]. Since the mechanism of their formation is still unknown, the aim of this work was to investigate the behaviour of wine monomeric and oligomeric and polymeric flavanols in the presence of SO2, through the evaluation of the kinetic parameters of the monomeric and dimeric flavanols sulfonation at the wine pH.The experimental design considered two different pH (3 and 4) and at five different temperature values (23, 30, 40, 50 and 60 oC), in order to study the reaction products obtained by SO2 addition to both monomeric (epicatechin and catechin) and dimeric flavanols (procyanidin B2 and procyanidin B3). The quantitative measurements were carried out by using a UHPLC-QTOF-MS instrument. The results demonstrated that [3]:a) the major sulfonation route that leads quickly and in good yields to monomeric 4β-sulfonated derivatives passes through the acid-catalysed depolymerisation of proanthocyanidins; b) monomeric flavanols lead with a significantly slower process to the same 4β-sulfonated products; c) kinetic data in our hands, in particular the temperature dependence of the observed rates, suggest the involvement of two completely different reaction mechanisms for the SO2 addition to dimeric and monomeric flavanol substrates; d) the direct sulfonation of epicatechin is slightly faster with respect to catechin.In conclusion, this new knowledge provides essential information in order to better understand tannin chemistry in food and predict or model the chemical/sensorial behaviour of wine or other food rich in proanthocyanidins.

DOI:

Publication date: September 10, 2021

Issue: Macrowine 2021

Type: Article

Authors

Panagiotis Arapitsas 1, Federico BONALDO 2, Fulvio MATTIVI 2, Graziano GUELLA 2

1 Fondazione Edmund Mach, San Michele all’Adige, Italy.
2 University of Trento, Trento, Italy.

Contact the author

Keywords

proanthocyanidins; tannins; sulfonation

Citation

Related articles…

Stability of 3-mercaptohexanol during white wine storage in relationship to must pre-fermentative fining

3-Mercaptohexanol (3MH) is a volatile thiol occurring in several white and red wines, where it can contribute to fruity attributes. Its content is typically high in wines from certain grape varieties, in particular Sauvignon blanc, where it is considered a varietal marker. The strong nucleophilic character of thiols makes 3MH rather unstable during wine storage, due to the presence of several strong electrophilic species. Among these electrophilics, those arising from the oxidation of flavan3-ols such as catechin and epi-catechin have been indicated as critical for 3MH stability. Accordingly, there is a generalized interest towards the ability of vinification practices to reduce 3MH loss during aging through the management of wine flavan-3-ols content.

Improved analysis of isomeric polyphenol dimers using the 4th dimension of trapped ion mobility spectrometry – mass spectrometry

Dehydrodicatechins have recently received attention as oxidation markers especially in grapes and wine. Their analysis mainly uses LC-MS/MS which is able to differentiate them from their natural isomers (dimeric procyanidins), based on specific fragments

The adaptative capacity of a viticultural area (Valle Telesina, Southern Italy) to climate changes

The viticulture aiming at the production of high quality wine is very important for the landscape conservation, because it allows to combine high farmer income with soil conservation

Study of the oenological potential of varieties resistant to cryptogamic diseases and drought to anticipate varietal selection in Occitanie

In the context of climate change and the growing need to reduce the use of phytosanitary products, the exploration of disease-resistant grape varieties and/or adapted to drought conditions is becoming crucial for the wine industry in certain regions of France, such as Occitanie. Currently, exploring the oenological potential of varieties by analyzing their biochemical composition before and after winemaking comes rather late in the varietal selection process.

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.