Macrowine 2021
IVES 9 IVES Conference Series 9 Evaluation of the sensory profile of doc douro red wines through sensory traditional single-point techniques and temporal dominance methods

Evaluation of the sensory profile of doc douro red wines through sensory traditional single-point techniques and temporal dominance methods

Abstract

No other agricultural product has a stronger relationship with the soil than wine. This study aimed to characterize the sensory profile of red wines from the Douro Demarcated Region (RDD) certified as DOC Douro, through the application of Quantitative Descriptive Analysis (QDA®) and Temporal Dominance of Sensations (TDS) sensory methods. QDA® provides a complete word description for all a product’s sensory properties. The TDS, which is relatively recent in the sensory field [1], allows to evaluation and description of the evolution of the dominant sensory perceptions during the tasting of a food product.Eighteen commercial wines from different producers were evaluated, six different samples representing each of the three sub-regions of the RDD. The panel had eighteen tasters, divided into trained and specialists. The statistical treatment was done using tools such as CATPCA and SEM for ADQ®, MANOVA, and ANOVA for TDS.The results showed that, in both methods, the wines from the three sub-regions have profiles with very corresponding characteristics in visual, olfactory, and taste aspects. The results also pointed to a more expressive relationship to the characteristics of the sub-regions and Touriga Franca, Touriga Nacional, and Tinta Roriz varieties than to the oenological practices. The olfactory profile was characterized by aromatic Fruity, Floral, and Balsamic notes, on the other hand, the taste was highlighted by Astringency and Acidity and again Fruity as the main mouth-aroma. In the second-order factorial analysis of SEM, carried out on ADQ®, the taste attributes showed greater weight in all models [2], reinforcing the results of the CATPCA [3], where the analyzes pointed out the taste attributes as those with the greatest contribution to the characterization of the sensory profile of wines. The integrated use of CATPCA and SEM techniques proved to be robust. As for TDS, the expert tasters were at ease in carrying out the evaluations, both concerning the suggested evaluation protocol, as well as the interface of the data acquisition software. Moreover, the use of MANOVA followed by ANOVA revealed statistically significant differences for the highest rate of maximum dominance. The Factor Analysis indicated homogeneity of the panels, presenting high factor weights. For trained tasters, the factor explains 89.716% of the total variance, for experts, 92.163%. The value of individual commonality is high, revealing that the component is adequate to describe the latent factorial structure among the tasters.

DOI:

Publication date: September 24, 2021

Issue: Macrowine 2021

Type: Article

Authors

Alice Vilela, Eduardo, AMORIM, Elisete, CORREIA

Chemistry Research Center (CQ-VR), Dept. of Biology and Environment, School of Life Sciences and Environment, University of Trás-os-Montes e Alto Douro, Vila Real, Portugal*-Enology, and Viticulture Master Student, Dept. of Biology and Environment, School of Life Sciences and Environment, University of Trás-os-Montes e Alto Douro, Vila Real, Portugal.- Center for Computational and Stochastic Mathematics (CEMAT), Dep. of Mathematics, IST-UL, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal.

Contact the author

Keywords

sensory profile, qda, tds, wine, doc douro

Citation

Related articles…

Impact of climate change on the viticultural climate of the Protected Designation of Origin “Jumilla” (SE Spain)

Protected Designation of Origin “Jumilla” (PDO Jumilla) is located in the Spanish provinces of Albacete and Murcia, in the South-eastern part of the Iberian Peninsula, where most of the models predict a severe impact of climate change in next decades. PDO Jumilla covers an area of 247,054 hectares, of which more than 22,000 hectares

Climate ethnography and wine environmental futures

Globalisation and climate change have radically transformed world wine production upsetting the established order of wine ecologies. Ecological risks and the future of traditional agricultural systems are widely debated in anthropology, but very little is understood of the particular challenges posed by climate change to viticulture which is seen by many as the canary in the coalmine of global agriculture. Moreover, wine as a globalised embedded commodity provides a particularly telling example for the study of climate change having already attracted early scientific attention. Studies of climate change in viticulture have focused primarily on the production of systematic models of adaptation and vulnerability, while the human and cultural factors, which are key to adaptation and sustainable futures, are largely missing. Climate experts have been unanimous in recognising the urgent need for a better understanding of the complex dynamics that shape how climate change is experienced and responded to by human systems. Yet this call has not yet been addressed. Climate ethnography, coined by the anthropologist Susan Crate (2011), aims to bridge this growing disjuncture between climate science and everyday life through the exploration of the social meaning of climate change. It seeks to investigate the confrontation of its social salience in different locations and under different environmental guises (Goodman 2018: 340). By understanding how wine producers make sense of the world (and the environment) and act in it, it proposes to focus on the co-production of interdisciplinary knowledge by identifying and foreshadowing problems (Goodman 2018: 342; Goodman & Marshall 2018). It seeks to offer an original, transformative and contrasted perspective to climate change scenarios by investigating human agency -individual or collective- in all its social, political and cultural diversity. An anthropological approach founded on detailed ethnographies of wine production is ideally placed to address economic, social and cultural disruptions caused by the emergence of these new environmental challenges. Indeed, the community of experts in environmental change have recently called for research that will encompass the human dimension and for more broad-based, integrated through interdisciplinarity, useful knowledge (Castree & al 2014). My paper seeks to engage with climate ethnography and discuss what it brings to the study of wine environmental futures while exploring the limitations of the anthropological environmental approach.

A better understanding of the climate effect on anthocyanin accumulation in grapes using a machine learning approach

The current climate changes are directly threatening the balance of the vineyard at harvest time. The maturation period of the grapes is shifted to the middle of the summer, at a time when radiation and air temperature are at their maximum. In this context, the implementation of corrective practices becomes problematic. Unfortunately, our knowledge of the climate effect on the quality of different grape varieties remains very incomplete to guide these choices. During the Innovine project, original experiments were carried out on Syrah to study the combined effects of normal or high air temperature and varying degrees of exposure of the berries to the sun. Berries subjected to these different conditions were sampled and analyzed throughout the maturation period. Several quality characteristics were determined, including anthocyanin content. The objective of the experiments was to investigate which climatic determinants were most important for anthocyanin accumulation in the berries. Temperature and irradiance data, observed over time with a very thin discretization step, are called functional data in statistics. We developed the procedure SpiceFP (Sparse and Structured Procedure to Identify Combined Effects of Functional Predictors) to explain the variations of a scalar response variable (a grape berry quality variable for example) by two or three functional predictors (as temperature and irradiance) in a context of joint influence of these predictors. Particular attention was paid to the interpretability of the results. Analysis of the data using SpiceFP identified a negative impact of morning combinations of low irradiance (lower than about 100 μmol m−2 s−1 or 45 μmol m−2 s−1 depending on the advanced-delayed state of the berries) and high temperature (higher than 25oC). A slight difference associated with overnight temperature occurred between these effects identified in the morning.

Assessment of climate change impacts on water needs and growing cycle on grapevine in three DOs of NE Spain

This study assessed the suitability of grapevine growing in three DOs (Empordà, Pla de Bages and Penedès) of Catalonia (NE Spain) over the 21st century. For this purpose, an estimation of water needs and agroclimatic and phenological indicators was made. Climate change impacts were estimated at 1 km pixel resolution using temperature and precipitation projections from several general circulation models (GCM) and two climate change scenarios: RCP 4.5 (stabilization scenario) and RCP 8.5 (worst-case scenario). Potential crop evapotranspiration (following FAO procedure) and a daily water balance considering soil water holding capacity were used to estimate actual evapotranspiration of vines and, finally, water needs. Dynamics would be similar in the three DOs studied although the magnitude of impact differs. Water needs would be 2 and 3 times greater (ranging from 0 to more than 1500 m3/ha) than current water needs at both climate change scenarios. Moreover, blooming date would advance from 3 to 6 weeks, harvest date from 1 to 2.5 months, resulting in growing cycles from 10 to 80 days shorter. It should also be noted that frost risk would decrease from 6 to 76%, the number of days with temperatures above 30ºC during ripening would rise from 48 to 500% and tropical nights (minimum temperature >20ºC) at ripening would increase from 28 to 150%, depending on the scenario and the DOs. The impacts of climate change in the three DOs could result in significant limitations for grapevine cultivation and wine production if adaptive strategies are not applied. This result could serve as a basis for the design of specific and particular adaptation strategies to improve and maintain vineyards in the DOs studied and could be extrapolated to similar DOs and regions.

Grapevine sugar concentration model in the Douro Superior, Portugal

Increasingly warm and dry climate conditions are challenging the viticulture and winemaking sector. Digital technologies and crop modelling bear the promise to provide practical answers to those challenges. As viticultural activities strongly depend on harvest date, its early prediction is particularly important, since the success of winemaking practices largely depends upon this key event, which should be based on an accurate and advanced plan of the annual cycle. Herein, we demonstrate the creation of modelling tools to assess grape ripeness, through sugar concentration monitoring. The study area, the Portuguese Côa valley wine region, represents an important terroir in the “Douro Superior” subregion. Two varieties (cv. Touriga Nacional and Touriga Franca) grown in five locations across the Côa Region were considered. Sugar accumulation in grapes, with concentrations between 170 and 230 g l-1, was used from 2014 to 2020 as an indicator of technological maturity conditioned by meteorological factors. The climatic time series were retrieved from the EU Copernicus Service, while sugar data were collected by a non-profit organization, ADVID, and by Sogrape, a leading wine company. The software for calibrating and validating this model framework was the Phenology Modeling Platform (PMP), version 5.5, using Sigmoid and growing degree-day (GDD) models for predictions. The performance was assessed through two metrics: Roots Mean Square Error (RMSE) and efficiency coefficient (EFF), while validation was undertaken using leave-one-out cross-validation. Our findings demonstrate that sugar content is mainly dependent on temperature and air humidity. The models achieved a performance of 0.65