 IVES 9 IVES Conference Series 9 From vineyard to bottle. Rationalizing grape compositional drivers of the expression of valpolicella aroma ‘terroir’

From vineyard to bottle. Rationalizing grape compositional drivers of the expression of valpolicella aroma ‘terroir’

Abstract

AIM: Valpolicella is a renowned Italian wine-producing region (Paronetto, 1981). Wines produced in its different sub-regions are anecdotally believed to be aromatically different, although there is no systematic study addressing the chemical bases of such diversity. Aroma is the product of a biochemical and technological series of steps (Kotseridis, et al., 1999), as well as one of the most important features in the expression of the geographic identity and sensory uniqueness of a wine. The aim of this study was to investigate the volatile chemical composition of wines obtained from grapes harvested in selected vineyards during three consecutive vintages, assess the existence of recurring patterns that could represent unique aroma chemical signatures and to identify key grape compositional features underling such aroma signature.

METHODS: Corvina and Corvinone grapes were harvested from five different vineyards located in two sub-regions within Valpolicella during three consecutive vintages. Winemaking was performed under standardized conditions. Free volatile compounds and glycosidic precursors were analysed with GC-MS analysis co. Sensory characteristics of the wines have been investigated through sorting tasks performed with semi-trained panel.

RESULTS: Application of multivariate data analysis techniques allowed to identify volatile chemical patterns representing the unique aroma chemical signature of the geographical origin of each wine regardless of vintages. The main drivers associated with these chemical signatures were terpenes (linalool, α-terpineol), norisoprenoids (vitispirane, TDN, TPB), and, unexpectedly some fermentation derived esters. Wines’ terpenes content was related with grapes terpenes pool. In particular variations in wine linalool content were strongly associated with the grape content of different linalool forms. Finally, in the case of esters, a strong correlation between grape content of yeast assimilable nitrogen (YAN) and wine ester content was observed, further broadening the boundaries of vineyard factors able to influence wine aroma. Patterns of odor similarities were observed during sensory evaluation, indicating a recurring association between geographical origin and occurrence of aroma compounds such as linear and cyclic terpenes, esters or norisoprenoids.

CONCLUSIONS:

This study provides evidence for the existence of volatile chemical signatures that are representative of geographical origin. Identification of grapes compositional characteristics related to the main drivers of wines chemical signature provides clues to support producers in identifying and managing appropriate vineyard and/or winemaking practices, in the quest of producing wines expressing their sense of place and ‘terroir’

DOI:

Publication date: September 10, 2021

Issue: Macrowine 2021

Type: Article

Authors

Giovanni Luzzini

University of Verona,Davide SLAGHENAUFI, University of Verona Maurizio, UGLIANO, University of Verona Jessica, SAMANIEGO-SOLIS, University of Verona Riccardo TEDESCHI, Azienda Agricola F.lli Tedeschi

Contact the author

Keywords

chemical signature of geographical identity, red wine aroma, valpolicella, terroir, crus

Citation

Effect of maceration conditions during the winemaking of withered Corvina grapes on wine polyphenols and anthocyanins

Amarone is an Italian red wine with worldwide recognition and high added value. In Amarone wines, grapes undergo a withering process before vinification; this leads to a modification in the concentrations of sugars, acids, and secondary metabolites.

Contribution of soil and atmospheric conditions to leaf water potential in grapevines

Etant lié au sol et aux conditions atmosphériques, le statut hydrique influence la physiologie de la vigne d’une part, mais joue aussi un role important en ce qui concerne la qualité du raisin et donc du vin d’autre part. Nous avons mesuré, dans la région de Stellenbosch, le statut hydrique sur des pieds de Sauvignon Blanc non irrigués, implantés sur 2 terroirs différents, l’un froid, l’autre plus chaud.

Update knowledge about the presence of condensed tannins in grapes and their contributions to astringency perception

Condensed tannin is a principle group of polyphenol compounds derived from grape, greatly contributing to the bioactivity and the sensory perception of wine. Condensed tannins present as a heterogeneous mixture in nature involving various degrees of both polymerization and galloylation. Even though multiple attempts focusing on fractionation of grape condensed tannins by solid-phase have been conducted over the past decades, few individual tannins have been purified and identified. Hence, our knowledge on grape and wine condensed tannin moleculars has to be limited at the several known monomeric, dimeric and trimeric proanthocyanidins

Application of satellite-derived vegetation indices for frost damage detection in grapevines

Wine grape production is increasingly vulnerable to freeze damage due to warming climates, milder winters, and unpredictable late spring frosts. Traditional methods for assessing frost damage in grapevines which combine fieldwork and meteorological data, are expensive, time-consuming, and labor-intensive. Remote sensing could offer a rapid, inexpensive way to detect frost damage at a regional scale. Remote sensing approaches were used to assess freeze damage in grapevines by evaluating satellite-derived vegetation indices (VIs) to understand the severity and spatial distribution of damage in several New York vineyards immediately after a frost event (May 17th-18th, 2023). PlanetScope 3m satellite images acquired before and after the freeze were used to map damage and measure changes in VIs for vineyards in the Finger Lakes region.

A fine-scale approach to map bioclimatic indices using and comparing dynamical and geostatistical methods

Climate, especially temperature, plays a major role in grapevine development. Several bioclimaticindices have been created to relate temperature to grapevine phenology (e.g. Winkler Index, Huglin Index, Grapevine Flowering Véraison model [GFV]).