IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Gamay And Gamaret Winemaking Processes Using Stems: Impact On The Wine Aromatic Composition.

Gamay And Gamaret Winemaking Processes Using Stems: Impact On The Wine Aromatic Composition.

Abstract

Stems may bring various benefits to the wine such as alcoholic reduction, color protection or improvement of the tannic intensity. Not much used on Swiss grape varieties, the aim of this study was to identify the relevance of using this type of winemaking in the case of Gamay and Gamaret red grape varieties. In this presentation, focus will be done on the aromatic compounds brought to the wine from the stems.
Gamay and Gamaret wines were made according to five modalities: fully destemmed used as control, 20% and 40% either whole grapes or stems added to the rest of the destemmed harvest. The influence of the stems on the wine chemical properties was measured using different classical FTIR and colorimetric methods (alcohol, acidity, pH, SO2 …). Volatile composition of wine was analysed by gas chromatography coupled to  a mass spectrometer (GC-MS). The analysis of compounds with an aroma impact by olfactometry completes these analyses. Sensory analysis were also performed in order to measure the impact on the wines.
To understand the influence of stems, stem extracts were obtained from the same harvest batch using a maceration under simulated alcoholic fermentation protocol. These extracts were also analysed by GC-MS-olfactometry. The analytical results show differences between the aromatic profiles of the Gamay and Gamaret stems alcoholic extracts. The presence of terpene alcohol with floral notes such as linalool, geraniol or α-terpineol are particularly present in the alcoholic extracts of Gamaret stems. Gamay stems extracts have a more complex volatile compounds profile with esters and alcohols (fruity notes) present in greater quantities.
The presence of stems at different percentages and form during winemaking also influences the general aromatic profile of the different modalities.
This study allows us to acquire knowledge about winemaking processes performed using non-destemmed grapes and their impact on the wine characteristics.

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Poster

Authors

Blackford Marie1,2, Comby Montaine1,2, Imhof Janina2,Roesle-Fuchs Julie2, Dienes-Nagy Ágnes1, Fuchsmann Pascal1, Lorenzini Fabrice1, Bourdin Gilles1 and Bach Benoit2

1AGROSCOPE
2Changins, Viticulture and oenology, HES-SO University of Applied Sciences and Arts Western Switzerland

Contact the author

Keywords

Stem, whole cluster, winemaking, aromatic compounds

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Try the GiESCO EcoMetaEthical Charter !

The sustainability of vineyards is a major issue. The choices proposed to date have major flaws such as the lack of scientific bases or the use of dangerous products such as copper. GiESCO has published a charter of best practices for the environment and for people adapted to various environments. The use of sustainably resistant grape varieties that produce quality wines plays a central role here. Often innovative cultivation systems associated with new technologies and based on scientific bases, guarantee respect for people and the environment. These proposals are brought together in a charter which is part of a meta-ethical approach to seeking consensual measures to ensure the sustainability of vineyards.

The use of plasma activated water in barrel disinfection: impact on oak wood composition

The use of barrels is a practice that improves the quality of wines. The porous structure of wood favors the accumulation of microorganisms that can deteriorate the quality of wines so that barrel cleaning and sanitizing treatments are essential. The burning of sulphur discs has been the most common practice in winemaking because ots biocide effect. Nevertheless, its effectiveness is still insufficient and it is harmful for human health.

Assessing the relationship between cordon strangulation, dieback, and fungal trunk disease symptom expression

Grapevine trunk diseases including Eutypa dieback are a major factor in the decline of vineyards and may lead to loss of productivity, reduced income, and premature reworking or replanting. Several studies have yielded results indicating that vines may be more likely to express symptoms of vascular disease if their health is already compromised by stress. In Australia and many other wine-growing regions it is a common practice for canes to be wrapped tightly around the cordon wire during the establishment of permanent cordon arms. It is likely that this practice may have a negative effect on health and longevity, as older cordons that have been trained in this manner often display signs of decay and dieback, with the wire often visibly embedded within the wood of the cordon. It is possible that adopting a training method which avoids constriction of the vasculature of the cordon may help to limit the onset of vascular disease symptom expression. A survey was conducted during the spring of two consecutive growing seasons on vineyards in South Australia displaying symptoms of Eutypa lata infection when symptomless shoots were 50–100 cm long. Vines were assessed as follows: (i) the proportion of cordon exhibiting dieback was rated using a 0–100% scale; (ii) the proportion of canopy exhibiting foliar symptoms of Eutypa dieback was rated using a 0–100% scale; (iii) the severity of strangulation was rated using a 0–4 point scale. Images were also taken of each vine for the purpose of measuring plant area index (PAI) using the VitiCanopy App. The goal of the survey was to determine if and to what extent any correlation exists between severity of strangulation and cordon dieback, in addition to Eutypa dieback foliar symptom expression.

The chances for using non-saccharomyces wine yeasts for a sustainable winemaking

Climate changes and the trend towards organic and more sustainable winemaking highlighted the need to use biological methodologies. The reduction in the use of SO2, the need of the reduction of ethanol content of wines and the now need to reduce or eliminate chemical phytosanitary products, have prompted the search for alternative practices.

Water dynamics of Touriga-Nacional grapevines trained in cordon and guyot systems under Mediterranean climate conditions

Aims: The aims of the present study were to (1) evaluate the water dynamics of Touriga-Nacional grapevines trained to spur pruned cordon and Guyot systems and (2) assess the effect of variable water availability in a commercial vineyard located in the Demarcated Douro Region (DDR), Portugal.