terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Wine odors: chemicals, physicochemical and perceptive processes involved in their perception

Wine odors: chemicals, physicochemical and perceptive processes involved in their perception

Abstract

The odors of wines are diverse, complex and dynamic and much research has been devoted to the understanding of their chemical bases. However, while the “basic” chemical part of the problem, namely the identity of the chemicals responsible for the different odor nuances, was satisfactorily solved years ago, there are some relevant questions precluding a clear understanding. These questions are related to the physicochemical interactions determining the effective volatilities of the odorants and, particularly, to the perceptual interactions between different odor molecules affecting in different ways to the final sensory outputs.

The understanding of perceptual interactions has been delayed to a large extent by the common misunderstanding that odorants and odors are the same thing. Odorants are, however, chemical entities -volatile molecules- able to impact the olfactory receptors, while odors are the sensory experiences encoded by odorants. A significant part of the code is nowadays known, and can be explained in terms of odor x odor interactions. These interactions can be competitive, cooperative, destructive and creative. Cooperative interactions are relevant because give rise to the concept of odor vector, establishing a key link between the chemical and sensory spaces. Different studies have shown that the nearly 80 main wine odorants form 35 different wine aroma vectors, classified into 10-different aroma categories. Yet, aroma vectors can further interact by creative interactions to form new aroma nuances. Some of these interactions have been identified and will be shown. Furthermore, destructive interactions can also take a major role in wine, since ethanol and the higher alcohols are strong aroma suppressors. These suppression effects are of the highest interest in wine dealcoholization.

Finally, it will be shown that physicochemical interactions with different matrix components are enough to change the volatilities of some odorants by factors between 2 and 4, more than enough to have sensory relevance.

Acknowledgement. Most of this research has been funded by the Spanish government (projects MYCIN PID2021-126031OB; MINECO AGL2017-87373)

DOI:

Publication date: October 20, 2023

Issue: ICGWS 2023

Type: Article

Authors

Vicente Ferreira

Laboratory for Aroma Analysis and Enology (LAAE), University of Zaragoza, Spain

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Irrigation frequency in four grapevine red varieties in Spain. Effect on must volatile composition

The irrigation water management in the vineyard is a crucial aspect to obtain sustainable quality production over time. Previous studies have set the water requirements to be applied in the vineyard at 30 % of the reference evapotranspiration (ET0), although there are no studies that settle the effects of the frequency of irrigation application on red varieties in Spain. The present study contemplates the application of deficit irrigation (30 % ET0) applying a weekly dose in a single irrigation (T07) or in two irrigation events (T03) per week. The study has been carried out in 2021-2022 with four red varieties in different Spanish wine regions: Garnacha Tinta (Badajoz), Tempranillo (Valladolid), Syrah (Albacete) and Mencía (Lugo). The effects of irrigation frequency on must volatile composition have been evaluated through GC-MS.

Effect of biological control agents on grapevine rhizosphere microbiome and grapevine defenses

Plant diseases are a major obstacle to crop production. The main approaches to battle plant diseases, consist of synthetic chemicals to attack infecting pathogens. However, concerns are increasing about the effects of chemicals in the environment, leading to an increase in the use of biocontrol agents (BCAs), due to their assets, such as, antagonism, and competition. In this study, we tested the hypothesis that the introduction of Bacillus subtilis PTA-271 (Bs PTA-271) and Trichoderma atroviride SC1 (Ta SC1) produce distinctive modifications in the composition and network structure of the grapevine rhizosphere microbial community, as well as grapevine induced defenses.

Comparison of the effects of hormone- and natural-based elicitors on key metabolic pathways in cv. Tempranillo

One of the most important effects of climate change in wine-growing areas is the advance of phenological stages, especially concerning early berry ripening. In the hottest seasons, this results in a lack of synchrony between sugar and phenolic ripeness. In order to cope with this fact, a general effort is being made by researchers and growers aiming at delaying ripening through different strategies. One of the proposed approaches is the application of elicitors. This study aims to assess the effect at the transcriptomic level of application of three elicitors (Vitalfit, Fruitel, and Protone) in Tempranillo.

Application of antagonistic Metschnikowia strains against Botrytis cinerea in vineyards 

Less and less chemical plant protection products are approved by the E U. Plant pathogenic fungi become increasingly resistant to the active ingredients that have been around for a long time. Besides, there is a valid demand for effective products that can be applied in organic cultivation.
We examined Metschnikowia strains under laboratory conditions in order to find effective strains against B. cinerea. The antimicrobial mechanism of these yeasts is based on the competition for the ferric ions from the environment. Metschnikowia cells release the pulcherriminic acid which chelates with Fe3+, forming the pigment pulcherrimin.

Effect of ultraviolet B radiation on pathogenic molds of grapes

The fungicidal effect of UV-C radiation (100-280 nm wavelength) is well known, but its applicability for the control of pathogenic molds of grapes is conditioned by its effect on the host and by the risks inherent in its handling[1].
As an alternative, the effect in vitro of UV-B radiation (280-315 nm) on the main pathogenic molds of grapes has been studied: Botrytis cinerea, Aspergillus niger, Penicillium expansum and Rhizopus stolonifer.