IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Stability of 3-mercaptohexanol during white wine storage in relationship to must pre-fermentative fining

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

Abstract

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.
In the present study, Lugana white wines obtained using different products for pre-fermentative fining (PVPP, vegetable proteins, potato proteins, casein), as well without any fining, were adjusted to 30 mg/L of free SO2, spiked with a known amount of 3MH and submitted to aging at 24°C in ermetically sealed vials in the presence of 7 mg/L of dissolved oxygen.  Flavanol content of must and wines was assessed by means of HPLC, whereas 3MH was analyzed after aging by means of GC-MS after derivatization with ethyl propiolate.
The type of fining induced significant differences in the content of must and wine flavan-3-ols, with combinations of PVPP and vegetable proteins giving the largest flavan-3-ol decrease compared to control. Upon aging, wines fined with combinations of PVPP and vegetable proteins resulted in reduced 3MH loss, highlighting the positive influence of certain types of fining on wine aroma stability. Conversely, larger 3MH losses were observed when pre-fermentative fining was conducted using casein.  
The results of these study highlights the importance of fine tuning pre-fermentative fining to increase wine aroma stability and shelf-life 

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Poster

Authors

Ugliano Maurizio1, Manara Riccardo1, Slaghenaufi Davide1, Massot Arnaud2 and Moine Virgine2

1Department of biotechnology, University of Verona 
2Biolaffort

Contact the author

Keywords

Fining, 3-mercaptohexanol (3MH), vegetable proteins, oxidation

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Viticultural landscape: history of a challenging coexistence between grapevines and humans 

Vitis vinifera is the most grown grapevine species, which originated about 6 million years ago in the trans-caucasian area as the ancestral (wild) type v. Vinifera spp. Sylvestris. On the other hand, the human being (homo sapiens) is much younger since he originated about 300.000 years ago in north africa.
Read More

Un modello di lavoro per lo studio dell’ up-grading tecnologico del vigneto nel Veneto Occidentale. Connettività degli attori e mappatura su dati avepa integrati con rilevamento speditivo e qualitativo

Il lavoro si prefigge di esaminare la propensione alla modernizzazione della viticoltura del Veneto Occidentale, letto attraverso la diffusione di forme di allevamento a sviluppo contenuto.

Read More

Different oxygen and sulphur dioxide concentrations in ‘Sauvignon blanc’ must: effect on the composition of the must and wine

The effects of different oxygen and sulphur dioxide additions to South African ‘Sauvignon blanc’ musts were investigated. Oxygen addition without SO2 protection led to lower levels of certain volatile thiols in the wines, with a corresponding decrease in certain phenols and glutathione concentrations.

Read More

A fine scale study of temperature variability in the Saint-Emilion area (Bordeaux, France)

As the quality and typicity of wine are influenced by the climate, it is essential to have a good knowledge of climate variability, especially with regard to temperature, which has a great impact on vine behavior and grape ripening.

Read More

From vineyard to bottle. Rationalizing grape compositional drivers of the expression of “Amarone della Valpolicella” terroir

Valpolicella is a famous Italian wine-producing region. One of its main characteristic is the intensive use of grapes that are submitted to post-harvest withering. This is rather unique in the context of red wine, especially for the production of a dry red wine such as Amarone. Amarone wines produced in Valpolicella different geographic origin are anecdotally believed to be aromatically different, although there is no systematic study addressing the chemical bases of such diversity. Aroma is the product of a biochemical and technological series of steps, resulting from the contribution of different volatile molecules deriving from grapes, fermentations, and reactions linked to aging, as well as one of the most important features in the expression of the geographic identity and sensory uniqueness of a wine.

Read More