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…

Yield prediction assessment before bloom and at veraison in a cv. Airén high yielding vineyard in Toledo (La Mancha, Spain)

Anticipation in the possible responses of grapevines to environmental variations is key to adjust field work in view of a more effective management. This idea has been the driving force behind the current work, which seeks to understand the interaction patterns of the vine with its habitat throughout the growing cycle.

South Africa’s top 10 Sauvignon blanc wines. How do the chemical and sensory profiles compare?

FNB Top 10 Sauvignon Blanc competition, presented by the Sauvignon Blanc Interest Group of South Africa and sponsored by First National Bank, is the country’s foremost platform for producers of this cultivar to showcase and benchmark their wines. Wines entered in the competition originated from all over the winegrowing regions of the country and the winning wines showed good representation of quality South African Sauvignon blanc wines. The ten selected wines were subjected to various chemical analyses including volatile thiol and methoxypyrazine determination, while the sensory profile of each wine was determined using projective mapping.

Extreme canopy management for vineyard adaptation to climate change: is it a good idea?

Climate change constitutes an enormous challenge for humankind and for all human activities, viticulture not being an exception. Long-term strategic changes are probably needed the most, but growers also need to deal with short-term changes: summers that are getting progressively warmer, earlier harvest dates and higher pH in musts and wines. In the last 10-15 years, a relevant corpus of research is being developed worldwide in order to evaluate to which extent extreme canopy management operations, aimed at reducing leaf area and, thus, limiting the source to sink ratio, could be useful to delay ripening. Although extreme canopy management can result in relevant delays in harvest dates, longer term studies, as well as detailed analysis of their implications on carbohydrate reserves, bud fertility and future yield are desirable before these practices can be recommended.

PHOTO OXIDATION OF LUGANA WINES: INFLUENCE OF YEASTS AND RESIDUAL NITROGEN ON VSCS PROFILE

Lugana wines are made from Turbiana grapes. In recent times, many white and rosé wines are bottled and stored in flint glass bottles because of commercial appeal. However, this practice could worsen the aroma profile of the wine, especially as regards the development of volatile sulfur compounds (VSCs). This study aims to investigate the consequences of exposure to light in flint bottles on VSCs profile of Lugana wines fermented with two different yeasts and with different post-fermentation residual nitrogen.

The geological and geomorphological events that determine the soil functional characters of a terroir

The geology of a region is deemed to be an important component of terroir, as it influences the shape of the landscape and the climate of vineyard. The nature of rock and the geomorphological history of a terroir affect soil physical and chemical composition through a dynamic interplay with the changes of climate, vegetation and other living organisms, as well as with man activities.