Macrowine 2021
IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2021 9 Grapevine diversity and viticultural practices for sustainable grape growing 9 Evaluation of glutathione content in four white varieties in the d.o. Ca. Rioja (Spain)

Evaluation of glutathione content in four white varieties in the d.o. Ca. Rioja (Spain)

Abstract

AIM: Glutathione is a tripeptide that is mainly found in reduced form in grapes. It generates during the maturation of the grape, increasing significantly after veraison [1]. It plays a relevant role in the prevention of oxidative processes due to its high antioxidant activity. Its content in the grape is influenced by many factors (variety, vintage, cultural practices, nitrogen nutrition …) [2]. In musts and wines, it undergoes modifications due to oxygen exposure, tyrosinase activity, maceration time, pressing, yeast strain…[3]. The aim of this work was to evaluate the content of glutathione in the grape of four white varieties: Tempranillo Blanco, Maturana Blanca, Garnacha Blanca and Viura.

METHODS: The study was carried out during three seasons (2017, 2018 and 2019) in a vineyard located in the D.O.Ca. Rioja (Spain). On the other hand, the influence of different vineyard locations on the content of this compound in the indicated varieties was also analyzed. Glutathione determination was carried out by HPLC by automatic derivatization in precolumn with OPA. The previous extraction in the grape was carried out with HCl/EDTA [4].

RESULTS: The results obtained showed important varietal differences in the glutathione content of the grape in the white varieties studied. The highest concentration was obtained in the Tempranillo Blanco variety, although without significant differences in comparison to Viura, while the lowest levels corresponded to Maturana Blanca and Garnacha Blanca. Also, the characteristics of the vintage also influenced its concentration, although the varietal differences were maintained. The location of the vineyard showed a variable effect depending on the vinifera, and the characteristics of the vintage in the case of Tempranillo Blanco.

CONCLUSIONS

These results confirm that the variety is one of the most influential factors in the glutathione content in grapes. Tempranillo Blanco has high levels of this compound, which can help preserve the quality of your wines.

DOI:

Publication date: September 2, 2021

Issue: Macrowine 2021

Type: Article

Authors

Juana Martinez

Instituto De Ciencias De La Vid Y Del Vino (Gobierno De La Rioja, Csic, Universidad De La Rioja),Laura, Alti, Instituto De Ciencias De La Vid Y Del Vino (Gobierno De La Rioja, Csic, Universidad De La Rioja)  Sara, Garcia, Instituto De Ciencias De La Vid Y Del Vino (Gobierno De La Rioja, Csic, Universidad De La Rioja) Elisa, Baroja, Instituto De Ciencias De La Vid Y Del Vino (Gobierno De La Rioja, Csic, Universidad De La Rioja)

Contact the author

Keywords

glutathione, grape, white varieties, location, season

Citation

Related articles…

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.

Viticultural zoning in D.O.C. Ribeiro (Galicia, NW Spain)

L’AOC Ribeiro est la plus ancienne de Galice (NO de l’Espagne), avec une aire de production potentielle de 3.200 ha. Situé dans la région centrale de la vallée du Miño, le Ribeiro a un climat de tipe maritime tempéré qui se correspond avec la zone climatique II de Winkler.

Reconstructing ancient microbial fermentation genomes from the wine residues of Herod, Roman king of Judea

The fortress of the Herodium, built towards the end of the first century BCE/ante Cristo, on the orders of Herod the Great, Roman client king of Judea, attests the expansion of Roman influence in the eastern Mediterranean. During archaeological excavations of the Herodium in 2017[1], a winery was discovered on the ground floor of the palace, with an assortment of clay vessels in situ, including large dolia – clay fermentation vessels each capable of fermenting up to 300-400 L of wine. Thanks to the recent progresses in the field of paleogenomics[2], we could analyse the organic material consistent with grape pomace at the bottom of these vessels, by extracting and sequencing the DNA using shotgun metagenomics and targeted capture, aiming for enrichment of DNA from fermentation associated microbes.

CIEDE2000 colour difference value as a parameter for tracing the ageing process on wood aged spirits

It is quite common nowadays to carry out analyses which allow to control the ageing of spirits that are aged in wood casks. Many control parameters have been previously studied, such as the concentration of different phenolic compounds or the Total Polyphenol Index, in order to better understand the ageing process of wood aged spirits. On the other hand, it is frequent to analyse as a physical parameter the colour of those spirit samples, by stating them as an array of three coordinates from various colour spaces as CIE L*a*b* or CIE L*C*H*.

Spatial suitability analysis for site selection of vineyards using biophysical models and computational intelligence

Developing a sustainable agricultural production system and acquiring the full potential of land resources requires employing land-use assessment. This entails knowledge of the climate, soil, and topography of the area of interest.