IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 From vineyard to bottle. Rationalizing grape compositional drivers of the expression of “Amarone della Valpolicella” terroir

From vineyard to bottle. Rationalizing grape compositional drivers of the expression of “Amarone della Valpolicella” terroir

Abstract

Valpolicella is a famous Italian wine-producing region. One of its main characteristic is the intensive use of grapes that are submitted to post-harvest withering.  This is rather unique in the context of red wine, especially for the production of a dry red wine such as Amarone. Amarone wines produced in Valpolicella different geographic origin 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, resulting from the contribution of different volatile molecules deriving from grapes, fermentations, and reactions linked to aging, 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 dry red passito wines obtained from withered grapes from different origins and vintages, and assess the existence of recurring patterns that could represent unique aroma chemical signatures. Comparison between wine volatile profiles and grape compositional data allowed to identify some key grape compositional features underling such aroma. Corvina and Corvinone withered grapes were harvested from five different vineyards located in two sub-regions within Valpolicella during three consecutive vintages (2017-2019). Winemaking was performed under standardized conditions Free volatile compounds and glycosidic precursors were analysed with GC-MS analysis.

Sensory characteristics of the wines have been investigated through sorting tasks performed with semi-trained panel. PCA analysis techniques allowed to identify volatile chemical patterns representing the aroma chemical signature of the geographical origin of each wine. Terpenes and norisoprenoids were the main drivers of vineyards aroma chemical signatures, but many other compounds such as vanillates, branched chain ethyl esters and acetate ester contributed significantly. The contribution of certain fermentative compounds to chemical signatures, like isoamyl acetate was also important. Patterns of odor similarities were observed during sensory evaluation, even if they were not always associated with geographical. Variations in wine terpenes content were associated with the grape content of different forms, mainly free. Finally a good correlation between grape content of yeast assimilable nitrogen  and wine isoamyl acetate content was observed, further broadening the boundaries of vineyard factors able to influence wine aroma.This study provides evidence for the existence of volatile chemical signatures that are representative of geographical origin even in wines from withered grapes. Azienda Agricola F.lli Tedeschi is acknowledged for financial support

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Poster

Authors

Luzzini Giovanni1, Slaghenaufi Davide1, Ugliano Maurizio1

1University of Verona

Contact the author

Keywords

Chemical signature of geographical identity; Valpolicella; Tipicality; Red wine aroma, terroir

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Caratterizzazione varietale della CV. Vranac del Montenegro: primi risultati

Questo studio ha permesso di raccogliere alcune informazioni sul profilo chimico della cultivar Vranac coltivata in Montenegro. L’uva ha mostrato di raggiungere un buon accumulo zuccherino

Drought affects vineyard soil microbiome: approach to select micro-organisms adapted to drought

Climate transition with frequent heat waves and long drought periods threatens grapevine productivity and wine quality in the Mediterranean regions. Microorganisms are known to contribute to plant fitness and to stimulate plant resilience against biotic and abiotic factors.
In this work, it was assessed the impact of long-term drought on soil microbiome associated to grapevine in open field in Alentejo, renowned Portuguese wine region.
Soil and plant tissues of drought tolerant Syrah cultivar exposed to three irrigation levels (100%- FI, 50%-DI ETc; rain-fed–NI) for 5 years were sampled for two years (2022-2023). Metabarcoding analysis of soil bacteria (16S V4 rRNA) and fungi (ITS sub-region) were integrated with soil physiochemical properties and leaves´ physiological data. Pre-dawn leaf water potential and stomatal conductance confirmed the imposed drought scenarios. Even though, α- and β-diversity of prokaryotic and eukaryotic microbial communities differed more by season than water availability, samples clustered according to soil water content and pH (p<0.05). Fungal communities show higher differences in the structure across treatments than bacteria. In 2023, 16 bacterial against 61 fungal ASVs were significatively different in abundance between NI and FI. Beijerinckiaceae, Bradyrhizobiaceae (Alphaproteobacteria) and Nocardioidaceae, Streptomycetaceae (Actinobacteria) families resulted to be significatively more abundant in NI, while Ascomycota, Basidyomicota and Mortierellomycota are the most important fungal phyla in NI. With culturomics data, this study aims to gather insights into how soil microbiome is remodelled under drought and contribute to select bacterial and fungal taxa with potential to mitigate drought stress in vineyards.

DNA and type of grain: which factor does better explain sensory differences of sessile and pedunculate oaks?

Sessile oak and pedunculate oak have shown several differences of interest for enological purposes. Tannic and aromatic composition among sessile oak or pedonculate oak has been well studied. Sessile oak is generally more aromatic than pedunculated, while the later is more tannic. This scientific point of view is rarely applied to classify oak in cooperages. Most coopers use the type of grain to distinguish wide and thin grain.

RED WINE AGING WITHOUT SO₂: WHAT IMPACT ON MICROBIAL COMMUNITY?

Nowadays, the use of food preservatives is controversial, SO2 being no exception. Microbial communities have been particularly studied during the prefermentary and fermentation stages in a context of without added SO2. However, microbial risks associated with SO2 reduction or absence, particularly during the wine aging process, have so far been little studied. The microbiological control of wine aging is a key issue for winemakers wishing to produce wines without added SO2. The aim of the present study is to evaluate the impact of different wine aging strategies according to the addition or not of SO2 on the microbiological population levels and diversity.

Nutrients and heavy metals in a vineyard soil under organic, biodynamic and conventional management

Promoting sustainable agricultural practices is one of the challenges of the last decades. Organic and biodynamic viticulture can be an alternative to intensive viticulture, furthermore contributing to reduction of impact on environment and human health and guaranteeing soil preservation and quality products1. The aim of this experimentation was to evaluate the medium and long-term effects of different agronomic practices in viticulture on nutrient availability and heavy metal accumulation in soil.