IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Sensory profiles and European Consumer Preference related to Aroma and Phenolic Composition of Wines made from Fungus Resistant Grape Varieties

Sensory profiles and European Consumer Preference related to Aroma and Phenolic Composition of Wines made from Fungus Resistant Grape Varieties

Abstract

New grape varieties with several resistance loci towards powdery and downy mildew allows to significantly reduce the use of fungicides. These fungus resistant grape varieties (PIWI from the German Pilzwiderstandsfähig) play a crucial role to reach the goal to lower pesticide use by 50% as requested by the European Green Deal for 2030. However, wine growers are reluctant to plant them due to a lack of experience in vinification and uncertainty how consumer perceive and purchase wines of these completely unknown varieties.
The objective of this study within the VITIFIT research consortium was to vinify different wine styles in two vintages from grapes of four white and three red PIWI. Most of them came from the same experimental site, where four classic varieties were planted as well. We regressed data obtained by descriptive analysis with hedonic ratings from German, French, Italian, Danish and Dutch consumers. Several consumer segments appeared having different drivers of preference, however all consumers disliked sour, astringent and green wines with less fruit and color. Wine professionals scored the same wines and judged the wines very similar to the consumers: 9% of PIWI wines were rated significantly better, 9% significantly inferior and in 82%, no difference occurred.
To unravel the molecular base we analysed aroma compounds in a non-targeted way as well as by targeted analysis by SIDA-GC-MS or LC-MS for monoterpenes, C13-norisoprenoids and polyfunctional thiols. Analysis of phenolic compounds covered indirect measurements such as Folin-C or Harbertson-Adams-Assay as well as targeted analysis by LC-MS or LC-DAD. In case of the Muscaris (PIWI) versus Muskateller comparison Muscaris wines were richer in cis-roseoxide, while linalool and α-terpineol were higher in Muskateller wines. A sensory napping analysis however, could not distinguish wines of both varieties. So far, no specific off-flavors could be detected in the new PIWIs as they are reported for old hybrid varieties. Although fungus resistance may relate to increased polyphenols in the grape skin, red wines made from PIWI did not show higher concentrations in general across the different winemaking styles.
Overall, making wines from grapes from the same or very similar vineyards, PIWIs delivered from a sensory and hedonic point of view equivalent or even superior wines. Using different winemaking styles allow fulfilling specific and varying sensory demands of European consumers. Combining these findings with the elsewhere reported improved sustainability in growing PIWIs, should convince a rising number of conventional and organic vintners to plant more PIWIs in the near future.

References

sensory evaluation, fungus resistant grape varieties, consumer, aroma compounds, polyphenols

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Weber Marc1, Vestner Jochen1 and Fischer Ulrich1

1Dienstleistungszentrum Ländlicher Raum (DLR) Rheinpfalz, Institute for Viticulture and Oenology

Contact the author

Keywords

List of different keywords (keyword1, keyword2, keyword3)

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Late frost protection in Champagne

Probably one of the most counterintuitive impacts of climate change on vine is the increased frequency of late frost. Champagne, due to its septentrional position is historically and regularly affected by this meteorological hazard. Champagne has therefore developed a strong experience in frost protection with first experiments dating from the end of 19th century. Frost protection can be divided in two parts: passive and active. Passive protection includes all the methods that do not seek to modify the vine’s environment or resistance at the time of frost. The most iconic passive protection in Champagne is the establishment of the individual reserve. This reserve allows to stock a certain quantity of clear wine during a surplus year to compensate a meteorological hazard like frost during the following years. Other common passive methods are the control of planting area (walls, bushes, topography), the choice of grape variety, late pruning, or the impact of grass cover and tillage. Active frost protection is also divided in two parts. Most of the existing techniques tend to modify vine’s environment. Most of the time they provide warmth (candles, heaters, windmills, heating cables…), or stabilise bud’s temperature above a lethal threshold (water sprinkling). The other way to actively fight is to enhance the resistance of buds to frost (elicitors). The Comité Champagne evaluates frost protection methods following three main axes: the efficiency, the profitability, and the environmental impact through a lifecycle assessment. This study will present the results on both passive and active protection following these three axes.

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…

Effects of graft quality on growth and grapevine-water relations

Climate change is challenging viticulture worldwide compromising its sustainability due to warmer temperatures and the increased frequency of extreme events. Grafting Vitis vinifera L.

Influence of weather and climatic conditions on the viticultural production in Croatia

The research includes an analysis of the impact of weather conditions on phenological development of the vine and grape quality, through monitoring of four experimental cultivars (Chardonnay, Graševina, Merlot and Plavac mali) over two production years. In each experimental vineyard, which were evenly distributed throughout the regions of Slavonia and The Croatian Danube, Croatian Uplands,

Phenolic composition of Tempranillo Blanco grapes changes after foliar application of urea

Our research aimed to determine the effect and efficiency of foliar application of urea on the phenolic composition of Tempranillo Blanco grapes. The field experiment was carried out in 2019 and 2020 seasons and the plot was located in D.O.Ca Rioja (North of Spain). The vineyard was Vitis vinifera L. Tempranillo Blanco and grafted on Richter-110 rootstock. The treatments were control (C), whose plants were sprayed with water and three doses of urea: plants were sprayed with urea 3 kg N/ha (U3), 6 kg N/ha (U6) and 9 kg N/ha (U9). The applications were performed in two phenological stages, pre-veraison (Pre) and veraison (Ver). Also, each of the treatments was repeated one week later. Control and treatments were performed in triplicate and arranged in a randomised block design. Grapes were harvested at optimum ripening stage. High-performance liquid chromatography was used to analyse the phenolic composition of the grapes. Finally, the results obtained from the analytical determinations – flavonols, flavanols and non-flavonoid (hydroxybenzoic acids, hydroxycinnamic acids and stilbenes) – were studied statistically by analysis of variance. The results showed that, in 2019, U6-Pre and U9-Pre treatments increased the hydroxybenzoic acid content in grapes, and also all foliar treatments applied at Pre enhanced the stilbene concentration. Moreover, U3-Ver was the only treatment that rose flavonol and stilbene contents in the Tempranillo Blanco grapes. In 2020, all treatments applied at Pre enhanced the flavonol concentration in grapes. Furthermore, U3-Pre and U9-Pre treatments increased stilbene content in grapes. Nevertheless, the hydroxybenzoic acid content was improved by U6-Ver and U9-Ver and besides, hydroxycinnamic acid concentration in grapes was increased by all treatments applied at Ver. In conclusion, the lower and highest dose of urea (U3 and U9), applied at pre-veraison, were the best treatments to improve the Tempranillo Blanco grape phenolic composition.