terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Prediction of aromatic attributes of red wines from its colour properties 

Prediction of aromatic attributes of red wines from its colour properties 

Abstract

Wine perception is a multisensory experience that makes use of the sight, smell, and taste senses. When wine is sensorially assessed, the stimulus received generates multiple signals that tasters convert into organoleptic descriptors. Colour is commonly the first attribute evaluated during wine tasting. Moreover, the colour properties provide the taster with a priori information of the wine’s aroma. This preconceived perception is later confirmed or denied during the aroma evaluation. The aim of this study was therefore to investigate if the wine’s colour properties contain information relevant to the aromatic expression of red wines. To simulate the colour perception of a wine taster, RGB images were taken from 50 wines in both a static position and after a fixed inclination of the wine holder was applied. The aroma properties of the wines were assessed using a tasting sheet adapted to the wine aroma evaluation method used for teaching activities. Attributes such as the main central note, secondary notes, primary and secondary groups of aromas and finally the specific aroma descriptors were collected. Two levels of intensity (low and high) were also assigned to the specific aroma descriptors. The aroma evaluation of the wines was conducted in dark glasses to avoid biases in the responses. After multivariate data analysis and feature extraction, the relevant information of the RGB images was correlated with the aromatic descriptors using neural networks techniques. The results obtained showed certain ability of the wine’s colour properties to predict some of the major aromatic descriptors, proving that relevant information to wine aroma is contained within the colour properties of the wines. This study reaffirmed the multisensory nature of wine tasting and the potential value of using colour properties together with aromatic information to replicate wine aroma from chemical data.  

DOI:

Publication date: October 4, 2023

Issue: ICGWS 2023

Type: Article

Authors

Jose Luis Aleixandre-Tudo1,2*, Samuel Verdú1: Raúl Grau1

1Instituto de Ingeniería de Alimentos (FoodUPV), Departamento de Tecnología de Alimentos, Universidad Politécnica de Valencia, Valencia, Spain
2South African Grape and Wine Research Institute (SAGWRI), Department of Viticulture and Oenology, Stellenbosch University, Stellenbosch, South Africa

Contact the author*

Keywords

multisensory experience, colour, RGB images, aroma, neural networks

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Wine racking in the winery and the use of inerting gases

The O2 uptake in the different winemaking processes is generally considered to be negative for the sensory characteristics of white and rosé wines. Wine racking is a critical point of O2 uptake, as the large surface area of the wine exposed during this operation and the inability to maintain an effective inert gas blanket over it.
The objective was to study O2 uptake during the racking of a model wine without using inert gases and to compare it with the purging of the destination tank with different inert gases.

Rootstock effect on Cabernet Sauvignon aromatic and chemical composition

Grape quality potential for wine production is strongly influenced by environmental parameters and agronomic factors. Several studies underline the rootstock effect on scions vegetative growth and berry composition [1] with an impact on wine quality. Rootstocks are promising agronomic tools for climate change adaptation and in most grape-growing regions the potential diversity of rootstocks is not fully used and only a few genotypes are planted. Moreover, little is known about the effect of rootstock genetic variability on the aromatic composition in wines.

Drought responses of grapevine cultivars under different environments

Using grapevine genetic diversity is one of the strategies to adapt viticulture to climate change. In this sense, assessing the plasticity of cultivars in their responses to environmental conditions is essential. For this purpose, the drought tolerance of Grenache, Tempranillo and Semillon cultivars grafted onto SO4 was evaluated at two experimental vineyards, one located in Valencia (Spain) and the other in Bordeaux (France). This was done by assessing gas exchange parameters, water relations and leaf hydraulic traits at the end of the season.

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].

Crown procyanidin quantification in red wines, rosé wines and Port wines

Condensed grape tannins play a major role in the organoleptic properties and quality of red wine. Recently, a new sub-family of macrocyclic condensed tannins has been identified in red wine and named “crown tannins”. Indeed, the first compound of the family identified and characterised by NMR was the crown procyanidin tetramer which is composed of a macrocyclic structure composed of four (-)-epicatechins link together by B-type interflavanoid linkage in the following an alternative sequences of C4-C8 and C4-C6 linkage. The 3D structure of this unusual crown procyanidin family reveals a central cavity in the molecule [1].