Evolution of grape aromatic composition in cv. Ugni blanc

Abstract

AIM: Cognac is a protected appellation of origin where world-famous brandies are produced. These brandies are obtained by the traditional double distillation of wines from Ugni blanc cultivar, which is the main variety planted. According to the Cognac Appellation, harvest can occur between 13 & 21 °Brix. To date the harvest is assessed by vine growers only by sugar & acidity ripeness without considering the evolution of the aromatic profile. Hence, the goal of this research is to study the behavior of the main volatile compounds of grapes in order to better conduct the harvest.

METHODS: Two vineyard plots during two consecutive vintages (2019, 2020) were used to collect different fractions of 30 whole bunches. The samples were collected every week from pea-size to over ripeness (>21 °Brix) and then were stored at – 40°C until further analysis. Berries were grounded according to the protocol as described in Poitou, 2016. Grape powder were obtained and then analyzed for free & total volatiles by SPME-GC/MS (Young et al. 2015 ; Poitou, 2016). Principal component analysis (PCA) was conducted on the means of all significantly different parameters to elucidate the differences between grapes according to the maturity stage (Agilent MassProfiler Pro).

RESULTS: The kinetics of the volatile compounds during maturation showed strong variations with multiple trends depending the stage. Linear increase (e.g β-damascenone) or decrease (e.g p-cymene) of volatiles and a peak for cis-3-hexenol at véraison were found. Similarly to previous studies (Poitou, 2016 ; Ferrari et al. 2012), aromatic compounds were found to exhibit the same pattern. According to Rosillo et al. 1999, Ugni blanc & Chardonnay presents similar aromatic properties with low concentration of monoterpenes. Finally, the analysis of total volatiles showed the presence of newly identified terpenes in Ugni blanc grapes.

CONCLUSION

These results gave new insights for Ugni blanc aromatic characterization. Identification of terpenes with the total volatile method concludes that they are in their glycosylated form in grapes. Thus, they may be released during fermentation or distillation and participate to the aromatic complexity of wine distillates. With climate change, sugar concentration is expected to increase and will decouple sugar/acidity balance and the aromatic maturity. Therefore, understanding the aromatic maturity of Ugni Blanc will help growers to adapt their harvest date.

DOI:

Publication date: September 2, 2021

Issue: Macrowine 2021

Type: Article

Authors

Amandine Bernier

Jas Hennessy & Co, rue de la Richonne – CS20020, 16101 Cognac Cedex, France,Julia, GOUOT, Unité de recherche Œnologie, EA 4577, USC 1366 INRA, ISVV, Université de Bordeaux, F33882 Villenave d’Ornon, France  Adeline, BARREAU, Jas Hennessy & Co, rue de la Richonne – CS20020, 16101 Cognac Cedex, France  Panagiotis, STAMATOPOULOS, Jas Hennessy & Co, rue de la Richonne – CS20020, 16101 Cognac Cedex, France  Xavier POITOU, Jas Hennessy & Co, rue de la Richonne – CS20020, 16101 Cognac Cedex, France

Contact the author

Keywords

aromatic potential, berry composition, maturity, ugni blanc

Citation

Related articles…

Rare earth elements distribution in grape berries

Rare Earth Elements (REEs) include 15 lanthanides, yttrium and scandium. Their occurrence in soil and plants seems to be closely tied to the geological composition of the underlying mother rock, to the physical and chemical properties of the soil and to the specific ability of the plant to take up and accumulate these microelements.

Vitivoltaics: overview of the impacts on grapevine performance, wine quality, design features and stakeholder perceptions

This multidisciplinary study investigates “”Vitivoltaics,”” where photovoltaic (PV) panels are integrated into vineyard systems to generate renewable energy while providing partial shade to grapevines.

Genetic identification of 200-year-old Serbian grapevine herbarium

Botanist Andreas Raphael Wolny collected a grapevine herbarium from 1812-1824 in Sremski Karlovci (wine region of Vojvodina, Serbia), which represents local cultivated grapevine diversity before the introduction of grape phylloxera in the region. The herbarium comprises over 100 samples organized into two subcollections based on berry colour (red and white varieties), totaling 47 different grape varieties. The objective of this study was to investigate the historical varietal assortment of Balkan and Pannonian winegrowing areas with long viticulture traditions.

The future of DMS precursors during alcoholic fermentation: impact of yeast assimilable nitrogen levels on the contents of DMSp in young wines

Some red wines develop a “bouquet” during ageing. This complex aroma is linked to quality by wine tasters1. The presence of dimethylsulfide (DMS) in those wines is implicated

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.