 IVES 9 IVES Conference Series 9 Monitoring the tawny port wine aging process using precision enology

Monitoring the tawny port wine aging process using precision enology

Abstract

AIM: Tawny Port wine is produced in the Douro Demarcated Region by blending several fortified wines in different aging stages. During the aging process in small wood barrels, the red wine color progressively develops into tawny, medium tawny, or light tawny. In this Port wine style, there are some special categories like Tawny Reserve, Tawny with Indication of Age (10, 20, 30, and 40 years), and “Colheita” that are commercialized worldwide. This last category is an exception, as these wines are from a single vintage [1]. In Tawny Port wine the oxidative aging process is multifactorial and critical for reaching the required quality. So, real-time monitoring of important intrinsic and extrinsic factors known to impact both wine quality and aging time are important to optimize and to manage the natural inconsistency among wines aged in diverse long-used wood barrels. This work shows the design, development, and implementation of a remote distributed system to monitor factors that are identified to be critical for the Tawny Port wine aging process.

METHODS: The Tawny Port wine aging process was monitored in two equal wineries – one of them with controlled temperature– in Vallegre, Porto S.A.. Barrels were instrumented with sensors to measure parameters during the aging process, specifically: pH, redox potential, dissolved oxygen, and temperature. The monitoring process was done using an RS-485 industrial network, which interconnects the mentioned sensors [2].

RESULTS: The distributed monitoring system was capable to detect differences among barrels and among the different storage conditions (controlled and room temperature). Redox potential and dissolved oxygen were the wine’s parameters where the differences among the different barrels were higher under the same storage conditions. Since the Tawny Port wine aging process is oxidative, a variation in the wine’s aging process among barrels is to be expected. Significant differences were detected in the oxygen consumption rate among the different barrels. Differences in the phenolic composition were also observed in the aged wine, both at controlled and room temperature

CONCLUSIONS

Results indicated that the distributed monitoring system was capable to detect variations among barrels and among both storage conditions: controlled and room temperature. Actually, redox potential and dissolved oxygen were the wine’s factors where the variances found were higher among wood barrels, while under the same storage conditions. This methodology is based on easy-to-use implanted systems, with the intention of giving an important contribution to other projects in the area of precision enology

Acknowledgment

The authors want to acknowledge FCT Portugal for funding the CQ – VR through the grant (UIDB/00616/2020 and UIDP/00616/2020), to project INNPORT “Otimização do processo de envelhecimento do vinho do Porto Tawny” and Vallegre Company.

DOI:

Publication date: September 10, 2021

Issue: Macrowine 2021

Type: Article

Contact the author

Keywords

precision enology, wine aging, instrumentation

Citation

Protected Designation of Origin (D.P.O.) Valdepeñas: classification and map of soils

The objective of the work described here is the elaboration of a map of the different types of vineyard soils that to guide the famers in the choice of the most productive vine rootstocks and varieties. 90 vineyard soils profiles were analysed in the entire territory of the Origen Denominations of Valdepeñas. The sampling was carried out in 2018 (June to October) by making a sampling grid, followed by photointerpretation and control in the field. The studied soils can be grouped into 9 different soil types (according to FAO 2006 classification): Leptosols, Regosols, Fluvisols, Gleysols, Cambisols, Calcisols, Luvisols and Anthrosols. A map showing the soil distribution with different type of soils has been made with the ArcGIS program. Regarding to the choice of rootstock, Calcisoles are soils with a high active limestone content, so the rootstocks used in these soils must be resistant to this parameter; Luvisols are deep soils with high clay content, so they will support vigorous rootstocks. Because the cartographic units are composed of two or more subgroups, with are associated in variable proportions, 9 different soil associations have been established; Unit 1: Leptosols, Cambisols and Luvisols (80%, 15% and 5% respectively); Unit 2: Cambisols with Regosols and Luvisols (40%, 30% and 30% respectively); Unit 3: Cambisols and Gleysols with Regosols (40%, 40% and 20% respectively); Unit 4: Regosols with Cambisols, Leptosols and Calcisols (40%, 30%, 15% and 15% respectively); Unit 5: Cambisols, Leptosols, Calcisols and Regosols (25% each of them); Unit 6: Luvisols with Cambisol and Calcisols (80%, 10% and 10% respectively); Unit 7: Luvisols and Calcisols with Cambisols (40%, 40% and 20% respectively); Unit 8: Calcisols with, Cambisols and Luvisols (80%, 10% and 10% respectively); Unit 9: Anthrosols. These study allow to elaborate the first map of vineyard soils of this Protected Designation of Origin in Castilla-La Mancha.

Caractérisation du terroir en Espagne : méthodologie de l’évaluation et de la validation

In recent years, there has been a growing interest in characterizing the ecological environment of vineyard production, and the growing need to delimit and characterize with precision the different homogeneous viticultural units. This has allowed the development of new studies which have as their objective the Vineyard Zoning. The delimitation and characterization of wine-growing areas poses specific problems in Spain, not only linked to the specific characteristics of the territory, but also to the size, distribution and index of viticultural occupation in the designations of origin.

Study of the evolution of tannins during wine aging by mass spectrometry monitoring of oxidation markers released after chemical depolymerization

Among the many compounds in wine, condensed tannins play an important role in the organoleptic properties of the products; they are partly responsible for astringency, bitterness and also contribute to the color. This research work aims to study the oxidation state of these bio-heteropolymers which is an important lock in the analysis of processed products in order to better control their quality. Indeed, their identification remains at present a challenge because of the large heterogeneity of their degrees of polymerization (DP) based on 4 monomers (epicatechin, catechin, epigallocatechin, epicatechin-3-O-gallate) thus multiplying the number of oxidation products.

FUNCTIONALIZED MESOPOROUS SILICA IS A VIABLE ALTERNATIVE TO BENTONITE FOR WINE PROTEIN STABILIZATION

The presence of grape-derived heat unstable proteins can lead to haze formation in white wines [1], an instability prevented by removing these proteins by adding bentonite, a hydrated aluminum silicate that interacts electrostatically with wine proteins leading to their flocculation. Despite effective, using bentonite has several drawbacks as the costs associated with its use, the potential negative effects on wine quality, and its environmental impact, so that alternative solutions are needed.

Definition and planning of viticultural landscapes case study in the “Côtes du Rhône Gardoises”

Les préoccupations actuelles autour des paysages viticoles vont au-delà des clichés promotionnels développés par les stratégies marketing. En effet, les paysages sont aujourd’hui au cœur d’une demande sociale croissante qui se traduit par différentes lois (la loi paysage de 1993, le paysage reconnu comme patrimoine commun de la nation par la loi n°95-101, la création du Conseil national du paysage par arrêté du 8/12/2000).