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…

Soil quality in Beaujolais vineyard. Importance of pedology and cultural practices

A pedological study was carried out from 2009 to 2017 in Beaujolais vineyard, to improve physical and chemical knowledge of soils. It was completed in 2016 and 2017 by the current study, dealing with microbial aspects, in order to build a reference frame for improved advice in soil management. Microbial biomass was measured on representative plots of the six most common soil types identified in Beaujolais and, for each soil type, on plots with different levels of the main impacting parameters: total organic carbon, pH, cation exchange capacity, extractable copper. A total of 59 soil samples were collected. Confirming the results of various trials carried out in Beaujolais over the past 20 years, the results of the present study showed that the soils were still alive, but exhibited a large variability of biological parameters, which appeared dependant on both pedological and anthropic factors. Therefore, a good interpretation of biological parameters and advice for vine growers must rely on a pedologically-based referential with differentiated main driving factors. For example, the control of pH is of primary importance in granitic soils and in no way organic matter addition can improve soil quality if pH is too low. Conversely, in calcareous soils, biological parameters are more directly affected by direct or indirect (cover crops for example) inputs of organic matter. The use of biological parameters, such as microbial biomass, is of great potential value to improve advice on agro-viticultural practices (soil management, fertilization, liming, etc.), basis of a sustainable wine production on fragile soils.

Cytochrome P450 CYP71BE5 from grapevine (Vitis vinifera) catalyzes the formation of the spicy aroma compound, (-)-rotundone

(-)-Rotundone, an oxygenated sesquiterpene, is a potent odorant molecule with a characteristic spicy aroma existing in various plants including grapes1. It is considered as a significant compound notably in wines and grapes because of its low sensory threshold (16 ng L-1 in red wine, 8 ng L-1 in water) and aroma properties. (-)-Rotundone was first identified in red wine made from the grape cultivar Syrah (regionally called Shiraz) in Australia1, and then it was found in several grape varieties such as Duras, Grüner Veltliner, Schioppettino and Vespolina from Europe2, 3. Several environmental factors affecting the accumulation of (-)-Rotundone during the grape maturation, were reported such as ambient temperature4, soil properties and topography5, soil moisture from irrigation and light exposure in the bunch zone by leaf removal2.

METHYL SALICYLATE: A TRENDY COMPOUND MARKER OF ZELEN, A UNIQUE SLOVENIAN VARIETY

The wine market interest for autochthonous varieties, particularly from less known wine regions, has significantly raised in the past few years. In that context, Slovenia, a small country from central Europe with a long winemaking tradition, is getting more and more attention, particularly through its range of unique regional varieties. Among them, Zelen, meaning “green” in Slovene, can only be found in the Vipava valley region, located on the western side of the country, near the border with Italy. When they are young, Zelen wines display very singular aromas reminiscent of rosemary, sage and white fruit. Despite its uniqueness, Zelen wine aromatic typicality is poorly documented in the literature.

Grapegrowing soils

The soil plays a key role in viticulture since it defines the planting depth, development and aeration of the root system and also controls the absorption of mineral elements and water conditions of the plant

Climate change and viticulture in Nordic Countries and the Helsinki area

The first vineyards in Northern Europe were in Denmark in the 15th century, in the southern parts of Sweden and Finland in the 18th century at 55–60 degrees latitude. The grapes grown there have not been made into wine, but the grapes have been eaten at festive tables. The resurgence of viticulture has started with global warming, and currently the total area of viticulture in the Nordic countries, including Norway, is estimated to be 400–500 hectares, most of which is in Denmark. Southern Finland, like all southern parts of Northern Europe, belongs to the cool-cold winegrowing area.