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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

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