Macrowine 2021
IVES 9 IVES Conference Series 9 Comprehensive exploration of wine aroma-related compounds as promoted by alternative vinification procedures in case of Zelen (Vitis vinifera L.) grapes processing

Comprehensive exploration of wine aroma-related compounds as promoted by alternative vinification procedures in case of Zelen (Vitis vinifera L.) grapes processing

Abstract

Not only vintner’s decisions in the vineyard, but also winemaker’s choices of technology approaches in the cellar play a significant role in the final wine style and quality. Whereas traditional technologies within chosen terroir are quite well explored and thus somehow predictable, there is no proper knowledge available on possible outcomes in case of implementing novel, alternative winemaking strategies. To reveal their effects on wine aroma compounds and sensory characteristics, two alternative strategies
(cryoextraction or addition of whole grape berries during last stages of fermentation) were compared to classical Vipava valley winemaking approach as normally used for an autochthonous variety Zelen. After separate vinification and bottling, all the experimental wines were subjected to semiquantitative metabolic profiling of volatile compounds (VOCs) by means of GC/MS and were then also sensorialy evaluated by pre-trained panel. The results showed in case of free VOCs, that the contact with whole grape berries during fermentation (WBF) promoted mainly isoamyl alcohol and linalool; whereas cryoextraction (CE) promoted more ethyl decanoate, ethyl hexanoate, ethyl lactate and ethyl octanoate as well as hexanoic and octanoic acids. Control on the other hand was the richest in hexyl acetate, isobutanol and 2-phenyl ethanol. In case of bound VOCs, WBF wines showed the highest concentrations in case of several alcohols (1-butanol, isoamyl alcohol, 1-pentanol, 3-methyl-2-butenol, 1-hexanol, benzyl alcohol), but interestingly a decrease or a trend toward decrease in most of the observed bound volatile compounds was noticed for CE. Finally, most of the analytical results were in consistence with the results of sensory evaluation outcomes. A comprehensive, targeted metabolomics profiling approach was thus shown to be a very useful tool to support the exploration of novel techniques in winemaking by offering an important new knowledge also to the producers. Key words: alternative vinification procedures, cryoextraction, fermenting in the presence of whole grape berries, Zelen (Vitis vinifera L.), free aroma compounds, bound aroma compounds, targeted metabolomics.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Melita Sternad Lemut*, Cesare Lotti, Cristele Delsart, Urska Vrhovsek

*University of Nova Gorica

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Determination of metallic elements in Chilean wines by atomic absorption spectroscopy and inductively coupled plasma–mass spectrometry

The chemical composition of wines depends on series of variables such as the type of grape, edaphoclimatic conditions, and viticulture and winemaking practices employed during production. Metallic elements play a significant role during winemaking (e.g. as catalysts of oxidation reactions) and have been previously employed for the classification of wines according to provenance. In this work, we focused on the analysis of metallic elements (K, Na, Ca, Zn, Cu, Fe, Mg, Mn, Ni, Cr, Al, Pb, Cd, Hg, Se, Co, Sn and As) in 145 Chilean wine samples (102 reds and 43 white wines), of seven grape varieties, and five of the major wine producing regions in Chile.

Novel contribution to the study of mouth-feel properties in wines

In general, there is a well-established lexicon related to wine aroma and taste properties; however mouth-feel-related vocabulary usually includes heterogeneous, multimodal and personalized terms. Gawel et al.
(2000) published a wheel related to mouthfeel properties of red wine. However, its use in scientific publications has been limited. The authors accepted that the approach had certain limitations as it included redundant and terms with hedonic tone and some others were absent. It is of high interest to generate a mouth-feel lexicon and finding the chemical compound or group of compounds responsible for such properties in red wine. In the present work a chemical fractionation method has been developed.

On the losses of dissolved CO2 from laser-etched champagne glasses under standard tasting conditions

Under standard champagne tasting conditions, the complex interplay between the level of dissolved CO2 found in champagne, its temperature, the glass shape, and the bubbling rate, definitely impacts champagne tasting by modifying the neuro-physico-chemical mechanisms responsible for aroma release and flavor perception. Based on theoretical principles combining heterogeneous bubble nucleation, ascending bubble dynamics and mass transfer equations, a global model is proposed (depending on various parameters of both the wine and the glass itself), which quantitatively provides the progressive losses of dissolved CO2 from laser-etched champagne glasses.

Effect of intra‐vineyard ripeness variation on the efficiency of commercial enzymes on berry cell wall deconstruction under winemaking conditions

Intra-vineyard variation grape berry ripening occurs within bunches, between bunches on the same vine and between vines. Although it is assumed that such variation also occurs at the grape berry cell wall level, no study to data has investigated in any depth. Here we have used a intra-vineyard panel design to investigate pooled bunches from six vines (per panel) in the context of a winemaking scenario. The dissected vineyard was harvested by separate panels, where each panel was then subjected to a standard winemaking procedure with or without the addition of three different enzyme preparations for maceration.

Estimation of chemical age of red wines with the use of Fourier transform infrared spectroscopy (FT-IR) and chemometrics

The color of a red wine is one of the most important parameters of its quality, giving much information on its status, such as the grape variety used or the winemaking style. As the result of a complex equilibrium between different forms of anthocyanins and polymerization reactions which occur over the course of time, color can also serve as an indication of a wines’ age. For this purpose the “chemical age” i and ii indexes have been introduced by Somers in 1977. The chemical age index i measures the color absorbance after the addition of acetaldehyde while chemical index ii provides an indication of how much of the total red pigments are resistant to SO2 bleaching.