terclim by ICS banner
IVES 9 IVES Conference Series 9 SENSORY PROFILES AND EUROPEAN CONSUMER PREFERENCE RELATED TOAROMA AND PHENOLIC COMPOSITION OF WINES MADE FROM FUNGUSRESISTANT GRAPE VARIETIES (PIWI)

SENSORY PROFILES AND EUROPEAN CONSUMER PREFERENCE RELATED TOAROMA AND PHENOLIC COMPOSITION OF WINES MADE FROM FUNGUSRESISTANT GRAPE VARIETIES (PIWI)

Abstract

Planting grape varieties with several resistance loci towards powdery and downy mildew reduces the use of fungicides significantly. These fungus resistant or PIWI varieties (acronym of German Pilzwiderstandsfähig) contribute significantly to the 50% pesticide reduction goal, set by the European Green Deal for 2030. However, wine growers hesitate to plant PIWIs as they lack experience in vinification and are uncertain, how consumer accept and buy wines from these yet mostly unknown varieties.

Grapes from four white and three red PIWI varieties were vinified in three vintages to obtain four different white and red wine styles, respectively plus one rosé. PIWI varieties as well as four reference Vitis vinifera varieties were planted in the same site. For each vintage, more than 70 winemakers compared the different PIWI styles with the Vitis vinifera reference wines. 70% of the comparisons yielded no significant differences, in 20% PIWI wines were superior and in 10% the reference wines. Regressing intensity ratings obtained by descriptive analysis with hedonic ratings from German, French, Italian, Danish and Dutch consumers, we could deduce drivers of liking in respect to the different cultural back ground. All consumers disliked sour, astringent and green expressions in wines while fruit and colour remained low. Floral and yellow fruits were preferred by French and German consumers, Danish liked thiol-derived flavours.

To unravel the molecular base aroma compounds were analysed non-targeted as well as targeted for monoterpenes, C13-norisoprenoids and polyfunctional thiols applying SIDA-GC-MS or LC-MS. Analysis of phenolic compounds was done by indirect methods such as Folin-C or Harbertson-Adams-Assay as well as targeted analysis by LC-MS or LC-DAD. Comparing Muscaris (PIWI) versus Muskateller Muscaris wines were richer in cis-rose oxide, while linalool and α-terpineol were higher in Muskateller wines. So far, no specific off-flavour could be detected in wines from PIWI varieties as it was the case for old hybrid varieties. Although fungus resistance may be related to grape skin polyphenols, in general neither white nor red PIWI wines revealed higher polyphenol concentrations, except for Muscaris and Cabernet Cortis. A fact which needs to be addressed in winemaking.

In conclusion, applying targeted winemaking allows to produce PIWI wines, which meets the expectations of European consumers in sensory terms, but also in respect to improved sustainability.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Article

Authors

Fischer Ulrich¹, Marc Weber¹, Ole Kohlmann¹, Maike Gentner¹, Jochen Vestner¹

1. DLR Rheinpfalz, Institute for Viticutlure and oenology, Breitenweg 71, 67435 Neustadt an der Weinstrass, Germany

Contact the author*

Keywords

fungus resistant grape varieties, consumer preference, aroma compounds, polyphenols

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

WHAT’S FUTURE FOR SANTORINI’S VITICULTURE IN THE CONTEXT OF CLIMATE CHANGE

The own-rooted vineyard of Santorini is a unique case of vineyard worldwide that is been cultivated for thousands of years. On the island’s volcanic soil, the vines are still cultivated with traditional techniques, which are adapted to the specific and extreme weather conditions that prevail on it. While climate change is a reality in the Mediterranean region, will Santorini vineyard endure its impact? The study of the traditional training systems, techniques and vine density, as well as the application of sustainable solutions (cover crops and use of kaolin etc.) revealed sustainable methods for the adaptation of the local viticulture to new climatic phenomena that tend to be more and more frequent in the region due to climate change.

SENSORY EVALUATION OF WINE AROMA: SHOULD COLOR-DRIVEN DESCRIPTORS BE USED?

The vocabulary used to describe wine aroma is commonly organized according to color, raising the question of whether they reflect the reality of olfactory perception. Previous studies have assumed this convention of color-aroma matching, and have investigated color’s influence on the perception of aroma only in dyed white wine or in red wine from particular places of origin. Here 48 white and red varietal wines from around the world were evaluated in black glasses then in clear glasses by a panel of wine experts, who gave intensity ratings for aroma attributes commonly used by wine professionals. In black glasses, aromas conventionally associated with white wine were perceived in the red wines, and vice versa.

CHEMICAL DRIVERS OF POSITIVE REDUCTION IN NEW ZEALAND CHARDONNAY WINES

According to winemakers, wine experts and sommeliers, aromas of wet stone, mineral, struck match and flint in white wines styles, such as those produced from Vitis vinifera L. cv. Chardonnay, are considered to be hallmarks of positive reduction.1,2 In recent years, the production of Chardonnay styles defined by aroma characteristics related to positive reduction has become more desirable among wine experts and consumers. The chemical basis of positive reduction is thought to originate from the concentration of specific volatile sulfur compounds (VSCs), including methanethiol (MeSH) imparting mineral and chalk notes,3 and benzenemethanethiol (BMT) responsible for struck match and flint.1,4

CHARACTERIZATION OF ENOLOGICAL OAK TANNIN EXTRACTS BY MULTI-ANALYTICAL METHODS APPROACH

Oak tannin extracts are commonly used to improve wine properties. The main polyphenols found in oak wood extracts are ellagitannins¹ that release ellagic acid upon hydrolysis and comprise numerous structures². Moreover, oak tannin extracts contain other compounds giving a complex mixture. Consequently, the official OIV method based on gravimetric analysis of the tannin fraction adsorbed on polyvinylpolypyrrolidone is not sufficient to describe their composition and highlight their chemical diversity.

S. CEREVISIAE AND O. ŒNI BIOFILMS FOR CONTINUOUS ALCOHOLIC AND MALOLACTIC FERMENTATIONS IN WINEMAKING

Biofilms are sessile microbial communities whose lifestyle confers specific properties. They can be defined as a structured community of bacterial cells enclosed in a self-produced polymeric matrix and adherent to a surface and considered as a method of immobilisation. Immobilised microorganisms offer many advantages for industrial processes in the production of alcoholic beverages and specially increasing cell densities for a better management of fermentation rates.