Macrowine 2021
IVES 9 IVES Conference Series 9 Impact of addition of fumaric acid and glutathion at the end of alcoholic fermentation on Cabernet-Sauvignon wine

Impact of addition of fumaric acid and glutathion at the end of alcoholic fermentation on Cabernet-Sauvignon wine

Abstract

Viticulture and oenology face two major challenges today, climate change and the reduction in the use of inputs. Climate change induces low acidity and microbiologically less stable wines (1), implying more important sulfur dioxide doses to protect wines. This is incompatible with the reduction of inputs. Fumaric acid (FA) is known for its high acidifying power and its bacteriostatic properties (2) and glutathione (GSH) for its antioxidant power (3). FA combined with GSH could solve acidity problems and reduction of sulfur dioxide in wine. The study aims to evaluate the impact of FA and/or GSH addition at the end of alcoholic fermentation (AF) and just before bottling on wine quality compared to sulfite free, sulfited wine control and tartaric acid (TA) acidified wine. This work only presents the impact of addition of FA and GSH at the end of AF on Cabernet Sauvignon wine. Micro-winemakings were conducted with high mature Cabernet Sauvignon grapes. 9kg of grapes were vatted in each tank with 60mg/L sulfur dioxide. Duplicated vats were treated with TA (2.5g/L), FA (2.5g/L tartaric acid eq.), with 50mg/L GSH, with FA (2.5g/L tartaric acid eq.) + GSH (50mg/L) and three tanks were untreated (controls). At bottling, control wines were mixed and half part was added with sulfur dioxide (80mg/L). Oenological parameters, color, phenolic compounds, antioxidant capacities were evaluated at the end of AF, the end of malolactic fermentation (MLF) and 3 months after bottling. A ranking test and sensory profiles were realized on three-months wines. TA and FA addition at end of AF induced a similar decrease of pH. Total acidity was slightly higher in tanks where FA was added. In these same tanks, the MLFs were stopped when they had already started or did not start: MLFs were delayed for 2-3 months. Wines treated with FA produced 100% more lactic acid than control and TA-acidified wines. Color differences were observed in three-months wines after AF addition. The sulfited control was the lightest with more yellow hue and the wines with added FA were the darkest ones. Total phenolic compounds (total phenolic index and Folin-Ciocalteu analysis) were slightly lower in wines treated with FA and/or GSH. Total tannins were not affected by treatments unlike total anthocyanins. Their content in wine treated with FA without GSH was the lowest. In contrast, addition of GSH had a protective effect on total free anthocyanins. Antioxidant capacities were similar in all wines. Concerning organoleptic quality of wines, the ranking test on overall quality did not show differences but FA acidified wine was the best ranked. Sensory profils highlighted that sulfited control was less intense with more yellow hue. Acidified wines, especially with TA, and GSH added wine were slightly more aromatic than control wines. Addition of FA at the end of AF (2.5g/L tartaric acid eq.) allowed to delay MLF and produced 100% more lactic acid than control wines.

DOI:

Publication date: September 14, 2021

Issue: Macrowine 2021

Type: Article

Authors

Claire Payan

Unité de recherche Œnologie, EA 4577, USC 1366 INRA, ISVV, Université de Bordeaux, F33882 Villenave d’Ornon, France and Hochschule Geisenheim University von Lade Straße, 65366 Geisenheim, Germany,Anne-laure GANCEL, Unité de recherche Œnologie, EA 4577, USC 1366 INRA, ISVV, Université de Bordeaux, F33882 Villenave d’Ornon, France  Monika CHRISTMANN, Hochschule Geisenheim University von Lade Straße, 65366 Geisenheim, Germany  Pierre-Louis TEISSEDRE, Unité de recherche Œnologie, EA 4577, USC 1366 INRA, ISVV, Université de Bordeaux, F33882 Villenave d’Ornon, France

Contact the author

Keywords

fumaric acid, glutathione, color, phenolic compounds, organoleptic quality

Citation

Related articles…

Geospatial trends of bioclimatic indexes in the topographically complex region of Barolo DOCG

Barolo DOCG is an economically important wine producing region in Northwest Italy. It is a small region of approximately 70 km2 gross area. The topography is very complex with steep sloped hills ranging in elevation from below 200 m to 550 m. Barolo DOCG wine is made exclusively from the Nebbiolo grape. Bioclimatic indexes are often used in viticulture to gain a better understanding of broader climate trends which can be compared temporally and geographically. These indexes are also used for identifying potential phenological timing, growing region suitability, and potential risks associated with expected climatic changes. Understanding how topography influences bioclimatic indexes can help with understanding of mesoscale climate behaviour leading to improved decision making and risk management strategies. The average monthly maximum and minimum temperatures, the Cool Night Index, the Huglin Index, and the monthly diurnal range (from July to October) were calculated using data from 45 weather stations within a 40 km radius of the Barolo DOCG growing area between the years 1996 and 2019. Linear and multiple regression models were developed using independent variables (elevation, aspect, slope) extracted from a digital elevation model to identify significant relationships. Bioclimatic indexes were then kriged with external drift using independent variables that showed significant relationships with the bioclimatic index using a 100 m resolution grid. The maximum monthly temperatures and the Huglin Index showed consistent significant negative relationships with elevation in all years. The minimum monthly temperatures showed no relationship with elevation but in some months a small but significant relationship was observed with aspect. Due to the lack of a relationship between minimum monthly temperatures and elevation compared to the significant relationship between maximum monthly temperatures and elevation, monthly diurnal range had a negative relationship with elevation.

How does aromatic composition of red wines, resulting from varieties adapted to climate change, modulate fruity aroma?

One of the major issues for the wine sector is the impact of climate change linked to the increasing temperatures which affects physicochemical parameters of the grape varieties planted in Bordeaux vineyard and consequently, the quality of wine. In some varietals, the attenuation of their fresh fruity character is accompanied by the accentuation of dried-fruit notes [1]. As a new adaptive strategy on climate change, some winegrowers have initiated changes in the Bordeaux blend of vine varieties [2]. This study intends to explore the fruitiness in wines produced from grape varieties adapted to the future climate of Bordeaux. 10 commercial single–varietal wines from 2018 vintage made from the main grape varieties in the Bordeaux region (Cabernet franc, Cabernet-Sauvignon and Merlot) as well as from indigenous grape varieties from the Mediterranean basin, such as Cyprus (Yiannoudin), France (Syrah), Greece (Agiorgitiko and Xinomavro), Portugal (Touriga Nacional) and Spain (Garnacha and Tempranillo), were selected among 19 samples using sensory descriptive analyses. Both sensory and instrumental analyses were coupled, to investigate their fruity aroma expression. For sensory analysis, samples were prepared from wine, using a semi preparative HPLC method which preserves wine aroma and isolates fruity characteristics in 25 specific fractions [3,4]. Fractions of interest with intense fruity aromas were sensorially selected for each wine by a trained panel and mixed with ethanol and microfiltered water to obtain fruity aromatic reconstitutions (FAR) [5]. A free sorting task was applied to categorize FAR according to their similarities or dissimilarities, and different clusters were highlighted. Instrumental analysis of the different FAR and wines demonstrated variations in their molecular composition. Results obtained from sensory and gas chromatography analysis enrich the knowledge of the fruity expression of red wines from “new” grape varieties opening up new perspectives in wine technology, including blending, thus providing new tools for producers.

How can historical cultivars mitigate the effects of climate change?

IFV, INRAe and the national network “Partenaires de la Sélection Vigne” representing 37 organizations from the different wine regions, have been working increasingly closely over the last 2 decades towards the preservation of the French varietal patrimony. There are approximately 600 patrimonial varieties according to INRAe and SupAgro Montpellier experts, including ancient cultivars (400) and intravarietal crossbreeds obtained since the 19th century. In the context of a drastic reduction in such varieties from the mid 1980’s in favor of mainstream varieties, it was essential to carry out an inventory of old vines and vineyards. INRAe Vassal collection plays a key role here as it holds the largest diversity available, along with a rich bibliography and herbariums, offering us the opportunity to document and double check the identity of a cultivar, consolidating the expertise of ampelographers. The work is carried out in several stages, from verifying the existence of a variety in a small region, through to rehabilitation. During this session, the authors present the process that leads to the official registration of a variety. After this, IFV selection center takes over to initiate the process of selection and propagation. A specific focus within regions such as the Alps, Champagne and the South-West will provide details of the full procedure. Bia, Bouysselet, Chardonnay rose, Mecle and the aptly named Tardif, are some of the cultivars that have followed this procedure. Furthermore, a recent regulation established by INAO on “varieties of interest for adaptation purposes” might boost uptake by growers. Since 2006, 36 historical cultivars have been registered. Most of these have been neglected in the past due to late maturity, lack of sugar and high titratable acidity at harvest time. Such characteristics are today considered as positive qualities, not only in mitigation of the effects of climate change, but also as an opportunity for restoring diversity…

Impact of changes in pruning practices on vine growth and yield

A gradual decline in vineyards has been observed over the past twenty years worldwide. This might be explained by the climate change, practices change or the increase of dieback diseases. To increase the longevity of vines, we studied the impact of different pruning strategies in four adult and four young vineyards located in France and Spain. In France, vineyards were planted with Cabernet franc on 3309C while Spanish trials were planted with Tempranillo grafted on 110R. Vegetative expression, yield, quality of berries and wood vessels conductivity were measured. The distribution of vegetative expression, yield and berry composition between primary and secondary vegetation were quantified. Finally, tomography was used to evaluate the implication of the treatments on sap flows.
First results show that i) the respectful pruning leads to an increase of 30 to 50% more secondary shoots than the aggressive pruning in France and between 15 and 20% in Spain, ii) there is no major effect on the yield over the first two years following the implementation of the new pruning practices, although the proportion of clusters from suckers is higher on the respectful pruning method. On young vines, the development of the trunk according to a respectful pruning leads to a loss of harvest 2 years after planting. This is due to the removal, on the future trunk, of the green suckers which carrying bunches. This operation carried out in spring rather than during winter pruning, would promote a better leaf / fruit balance when the plant comes into production, and could lead to better hydraulic conduction in the vessels of the trunk. Maintaining these trials for several years will provide more robust data to assess the impact of these practices on the vines over the long term.

Modeling island and coastal vineyards potential in the context of climate change

Climate change impacts regional and local climates, which in turn affects the world’s wine regions. In the short term, these modifications rises issues about maintaining quality and style of wine, and in a longer term about the suitability of grape varieties and the sustainability of traditional wine regions. Thus, adaptation to climate change represents a major challenge for viticulture. In this context, island and coastal vineyards could become coveted areas due to their specific climatic conditions. In regions subject to warming, the proximity of the sea can moderate extremes temperatures, which could be an advantage for wine. However, coastal and island areas are particular prized spaces and subject to multiple pressures that make the establishment or extension of viticulture complex.
In this perspective, it seems relevant to assess the potentialities of coastal and island areas for viticulture. This contribution will present a spatial optimization model that tends to characterize most suitable agroclimatic patterns in historical or emerging vineyards according to different scenarios. Thanks to an in-depth bibliography a global inventory of coastal and insular vineyards on a worldwide scale has been realized. Relevant criteria have been identified to describe the specificities of these vineyards. They are used as input data in the optimization process, which will optimize some objectives and spatial aspects. According to a predefined scenario, the objectives are set in three main categories associated with climatic characteristics, vineyards characteristics and management strategies. At the end of this optimization process, a series of maps presents the different spatial configurations that maximize the scenario objectives.