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…

Atypical aging and hydric stress: insights on an exceptionally dry year

Atypical aging (ATA) is a white wine fault characterized by the appearance of notes of wet rag, acacia blossoms and naphthalene, along with the vanishing of varietal aromas. 2-aminoacetophenone (AAP) – a degradation compound of indole-3-acetic acid (IAA) – is regarded as the main sensorial and chemical marker responsible for this defect. About the origin of ATA, a stress reaction occurring in the vineyard has been looked as the leading cause of this defect. Agronomic, climatic and pedological factors are the main triggers and among them, drought stress seems to play a crucial role.[1]

Possible methods of adaptation to the effects of climate change in the Tokaj Wine Region 

Viticulture’s adaptation to the harmful effects of climate change is globally the biggest challenge of the near future. Short, extremely intensive rainfalls and longer periods of drought are getting more frequent in the Tokaj Wine Region, where the majority of the vineyards are cultivated on steep slopes. Hence, erosion has high risk, especially when combined with the loess-based soils on about ten percent of the region. The environmentally beneficial cover crop and mulch usage can effectively reduce the risk of erosion, according to research done by the Tokaj Wine Region Research Institute of Viticulture and Oenology.

Effect of foliar application of urea and nano-urea on the cell wall of Monastrell grape skins

The foliar application of urea has been shown to be able to satisfy the specific nutritional needs of the vine as well as to increase the nitrogen composition of the must. On the other hand, the use of nanotechnology could be of great interest in viticulture as it would help to slow down the release of urea and protect it against possible degradation. Several studies indicate that cell wall synthesis and remodeling are affected by nitrogen availability.

Effect of riboflavin on the longevity of white and rosé wines

Light is a fundamental part at sales points which influences in the conservation of wines, particularly in those that are sold in transparent glass bottles such as rosé wines and increasingly white wines. The photochemical effect known as “light-struck taste” can cause changes in the aromatic characteristics of the wine. This “light-struck taste” is due to reactions triggered by the photochemical sensitivity of riboflavin (RBF).

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.