 IVES 9 IVES Conference Series 9 European consumer preference for wines made from fungus resistant grape varieties

European consumer preference for wines made from fungus resistant grape varieties

Abstract

Fungus resistant grape varieties (FRGV or PIWI) offer many benefits such as less pesticide use or premium prices for enhanced sustainability. Still, winemakers are concerned about inferior wine quality. This study evaluates how European wine consumers assess wines made from new FRGVs in comparison to traditional V. vinifera varieties. Most of them were grown in the same vineyard. Four white (Calardis Blanc, Muscaris, Sauvignac, Cabernet Blanc) und three red (Satin Noir, Cabernet Cortis, Laurot) FRGV were compared to Riesling, Sauvignon blanc, Muskateller, Cab. Sauvignon and Merlot. For each FRGV, different styles were vinified using standardized protocols. The 28 most representative wines were selected, including the V. vinifera equivalents. 72 wine experts assessed their overall quality and the wines were mailed in 30 ml bottles to 118 German, 32 Danish and 27 French consumers, including a standardised wine glass. In a “home use test” consumers evaluated hedonic liking in 6 sessions. All wines were characterized by descriptive analysis using a trained panel (n=19 judges x 2 replications).All FRGV wines performed equally well as the V. vinifera wines. One consumer segment preferred yellow fruit and oaked white wines, which was linked to 12 h of skin contact. Consumers from all countries favoured tropical fruit aromas along with a sweetness (4-6 g/L sugar). Sauvignac and Cabernet Blanc wines from early harvest were rejected by consumers from all countries due to a vegetative flavour and sourness.Consumer varied more regarding red wines. A large consumer segment preferred the fruity and less tannic thermo-vinified wines, especially of Satin Noir. In contrast, harsh and bitter tannins of Cabernet Cortis were refused. A second segment preferred dark coloured red wines, such as Laurot and Satin Noir. Particularly the Laurot wines had similar sensory profiles and hedonic ratings as Merlot, indicating a good FRGV substitute. Bleeding and use of oak increased consumer acceptance, especially in France. Rosé wines of all red cultivars were equally preferred by all consumers.Due to equal preferences for FRGV and V. vinifera wines by consumers and experts, concerns regarding wine quality can be dismissed. FRGVs may be offered as more sustainable sensory “copies” of V. vinifera wines or in a completely different style using low intervention winemaking.

DOI:

Publication date: September 24, 2021

Issue: Macrowine 2021

Type: Article

Authors

Marc Weber, Ole KOHLMANN, Ulrich FISCHER,

DLR Rheinpfalz, Neustadt, Weincampus Neustadt

Contact the author

Keywords

fungus resistant grape varieties, piwi, consumer preference, sensory evaluation, wine styles

Citation

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A predictive model of spatial Eca variability in the vineyard to support the monitoring of plant status

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Impact of geographical location on the phenolic profile of minority varieties grown in Spain. II: red grapevines

Because terroir and cultivar are drivers of wine quality, is essential to investigate theirs effects on polyphenolic profile before promoting the implantation of a red minority variety in a specific area. This work, included in MINORVIN project, focuses in the polyphenolic profile of 7 red grapevines minority varieties of Vitis vinifera L. (Morate, Sanguina, Santafe, Terriza Tinta Jeromo Tortozona Tinta) and Tempranillo) from six typical viticulture Spanish areas: Aragón (A1), Cataluña (A2), Castilla la Mancha (A3), Castilla –León (A4), Madrid (A5) and Navarra (A6) of 2020 season. Polyphenolic substances were extracted from grapes. 35 compounds were identified and quantified (mg subtance/kg fresh berry) by HPLC and grouped in anthocyanins (ANT) flavanols (FLAVA), flavonols (FLAVO), hydroxycinnamic (AH), benzoic (BA) acids and stilbenes (ST). Antioxidant activity (AA, mmol TE /g fresh berry) was determined by DPPH method. The results were submitted to a two-way ANOVA to investigate the influence of variety, area and their interaction for each polyphenolic family and cluster analysis was used to construct hierarchical dendrograms, searching the natural groupings among the samples. Sanguina (A3) had the most of total polyphenols while Tempranillo (A5) those of ANT. Sanguina (A2) and (A3) reached the highest values of FLAVO, FLAVA and AA. These two last samples had also the maximum of AA. The effect cultivar and area were significant for all polyphenolic families analyzed. A high variability due to variety (>50%) was observed in FLAVA and the maximum value of variability due to growing area was detected in AA (86.41%), ANT and FLAVO (51%); the interaction variety*zone was significant only for ANT, FLAVO, EST and AA. Finally, dendrograms presented five cluster: i) Sanguina (A2); ii) Sanguina (A3); iii) Tempranillo (A5); iv) Tempranillo (A3); Terriza (A3,A5), Morate (A5,A6); v) Santafé (A1,A6); Tortozona tinta (A1,A3,A6); Tinta Jeromo (A3,A4).

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