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…

Molecularly imprinted polymers: an innovative strategy for harvesting polyphenoles from grape seed extracts

Multiple sclerosis (MS) is a multifactorial autoimmune disease associating demyelination and axonal degeneration developing in young adults and affecting 2–3 million people worldwide. Plant polyphenols endowed with many therapeutic benefits associated with anti-inflammatory and antioxidant properties represent highly interesting new potential therapeutic strategies. We recently showed the safety and high efficiency of grape seed extract (GSE), a complex mixture of polyphenolics compounds comprising notably flavonoids and proanthocyanidins, in an experimental autoimmune encephalomyelitis (EAE) mouse model of MS.

Foliar application of urea improved the nitrogen composition of Chenin grapes

The nitrogen composition of the grapes directly affects the developments of alcoholic fermentation and influences the final aromatic composition of the wines. The aim of this study was to determine the effect and efficiency of foliar applications of urea on the nitrogen composition of grapes. This study was carried out during 2023 vintage and in the Chenin vineyard located in Estacion Experimental Mendoza (Argentina). Three urea concentrations 3, 6 and 9 Kg N/ha (C1, C2, and C3, respectively) and control (T) were applied in this vineyard at veraison. In all solutions were added 1ml/l of Tween 80 ® surfactant.

Distribution and sensory impact of new oak wood-derived compounds in wines

Despite the numerous research studies carried out in recent years, the study of wine aroma remains of great interest due to its complexity. Wine maturation in oak barrels is described as an important step in the production of quality wines. In fact, oak wood develops several aromatic nuances through its toasting which can be released into the wine. A great deal of work has been performed in order to identify the wood-derived volatile compounds that contribute to wine aroma (e.g., whisky-lactone, maltol, eugenol, guaiacol, vanillin).

Photoprotective extracts from agri-food waste to prevent the effect of light in rosé wines 

Light is responsible for adverse reactions in wine including the formation of unpleasant flavors, loss of vitamins or photodegradation of anthocyanins. Among them, the riboflavin degradation leads to the formation of undesirable volatile compounds, known as light-struck taste. These photo-chemical reactions could be avoided by simply using opaque packaging. However, most rosé wines are kept in transparent bottles due to different commercial reasons. Some agri-food waste extracts have been studied for their photoprotective action which turn to be highly correlated with phenolic content [1].

Phenolic composition profile of cv. Tempranillo wines obtained from severe shoot pruning vines under semiarid conditions

One of the limitations of vineyards in warm areas is the loss of wine quality due to higher temperatures during the grape ripening period. In order to adapt the vineyards to these new climatic conditions, a possible solution is to delay the ripening process of the grapes towards periods with milder temperatures, by means of management practices and thus improve the quality of the fruit and the wine produced. The technique of severe shoot pruning (SSP) has proven useful in achieving this objective.